DAILY REVISION (CHEMISTRY) (X)

13/5/22

1) State what is mean by the term 'periodic properties' of elements.

2) explain the meaning of the following terms :

A) atomic size

B) Ionization potential.

C) electron affinity.

D) electronegativity.

 state the factors which influence or affect each of the above periodic properties stated in above.

3) state two differences in nature or properties between elements of group IA and VIIA.

4) Name the following:

A) An element in period 3 whose electron affinity is zero.

B) an alkali metal other than Sodium and potassium.

C) the group in the periodic table which has three vertical columns.

D) An alkaline earth metal.

E) an element in period-2 having zero valency.

5) Arrange the following elements as per the instructions in the bracket:

A) Boron, carbon, beryllium, Lithium (as per decreasing order of atomic size)

B) bromine, chlorine, fluorine, iodine (as per decreasing order of electron affinity)

C) Silicon, sulphur , aluminium, chlorine (as per increasing order of electronegativity).

6) Give reasons for the following:

A) electron affinity is considered a periodic property.

B) increase nuclear charge, increases the electron affinity of the element.

C) atoms with the high Ionization potential tend to gain electrons.

D) Ionization potential decreases down a group in the modern Periodic table.

7) A) Name the halogen in group 7A of period 3 of the periodic table.

B) give the electronic configuration of the halogen stated in A above

C) state the character of the oxide of the halloween stated in about is the halogen stated in A above

D) Is the halogen stated in A an oxidizing agent or reducing agent. Give reason for the same.

E) name a covalent hydride obtained from halogen.

F) name an electrovalent and a covalent compound formed between the halogen and a metal and the halogen and a neutral gas respectively.

G) Draw the electron dot diagram to represent a molecule of the halogen state in A above.

9/5/22

1) a) The element at the bottom of a group is expected to show__ metallic characters than the element at the top of a group (less/ more)

b) The similarities in the properties of elements in a group is because they have the same __ (electronic configuration, number of outer electrons).

c) The properties of elements are periodic function of their___ (mass number/Atomic number)

d) Moving across a___ of periodic table, the elements show increasing ____ character (group/ period/ metallic/nonmetallic)

2) Carbon(At no. 6) and nitrogen(At. no 7) belong to same period of periodic table. Write down the 

a) electronic configuration of carbon and the group to which it belongs.

b) electronic configuration of nitrogen and the group to which it belongs.

c) Name one more element which is in the same group as nitrogen.

3) a) how many periods are in Mendeleef's periodic table ?

b) how many groups are in Mendeleef's periodic table ?

c) how many groups consist of normal elements and Transition Elements in Mendeleef's periodic table.

d) Why were some gaps left in Mendeleef's periodic table?

4) 

I        II    III       IV     V    VI     VII       0

lith Car oxygen L                         neon

X                        E     G              Q

Y                                                R

Z                                                T

In the periodic table given above, lithium, carbon, Oxygen and neon are placed in their correct positions. The position of 9 other elements is represented by letters. These letters are not the symbols of elements concerned. Answer the following questions.

a) write the letter for most reactive metal.

b) write the letter for most nonmetal.

c) Name the family of elements represented L, Q, R, T.

d) Name one element in group II, III, V.

e) Name the elements represented by the letters E and G respectively.

f) Write the structural formula of chloride of E.

5) a) What is the position of the zero group in long form of periodic table?

b) which of the elements in the pairs given below will have smaller atomic size?

 i) sodium or magnesium

 ii) nitrogen nitrogen or Phosphorus 

c) With reference to second period of periodic table, name an element 

 i) which has the largest atomic volume ?

ii) Which has smallest atomic volume?

d) Atomic number of an element is 18.

 i) State the group number to which this element belongs.

ii) state the period of this element.

e) An element M has atomic number 19. Answer the following questions:

i) is the element a metal or a non metal

ii) is the element more reactive than calcium or less ?

iii) Write the formula of sulphate of the element.

6) The sentences given below are taken from the long form of Periodic Table. fill in the blank spaces with appropriate words from the list of words given below:

 List of words: lanthanides, separated, transition, normal, 18, zero, metallic, non-metallic.

a) the subgroups A and B are__ in this table.

b) The___ elements are accommodated in the middle of table.

c) there are ___vertical columns for long period.

d) the strongly___ elements occupy group IA and IIA respectively on the left transition elements.

e) The ___ elements are placed on right hand side of the transition elements.

f) The rare gases are placed in__ group at the end.

g) the elements occupying left and right wing groups of periodic table are called ___elements.

h) the actinides and ___ are kept outside the periodic table to Mark their particular properties.

7) Given below is the part of periodic table:

Li        Be       B        C      N      O       F

Na      Mg      Al       Si     P       S      Cl

a) How does metallic character of an element change as one moves from 

i) left to right in a period ?

ii) Top to bottom in a group?

b) How does the valency of elements change with respect to hydrogen as one moves from left to right in a period ?

c)i) what is the valency of the element Si ?

ii) will it form a covalent or electrovalent bond with hydrogen which is the most metallic ?

d) Which is the

i) Most metallic element in the above table ?

ii) most non metallic element in the above table?

e) By drawing a dot diagram show the reaction between the elements named in (4) (a) and (b).

22/4/22

1) A) State the element other than hydrogen in periodic I of the modern Periodic Table.

B) name the element present in period 3 which belongs to the same group to that of the element stated in (A) above.

C) State the electronic configuration of the element stated in (B) above

2)A) explain the term periodic properties

B) state the periodic property of an element which

 a) decrease on moving from left to right in a period.

 b) increases on moving down a group in a period.

3) Compare the elements of group IA with elements of group VII A with respect to

A) number a valence electrons.

B) valency.

C) conduction of electricity.

D) oxidising/ reducing nature.

E) metallic/non metallic character

20/4/22

1) A) State the number of non metallic elements in period 2 of the Modern Periodic Table.

B) Name the metalloid in period 3 of the Periodic Table.

C)  Which of the three elements- Beryllium, boron or Lithium has the largest atomic size.

D) State the group of Periodic Table to which the elements- Fluorine, chlorine and bromine belong.

2) A) Define the periodic property 'atomic size'. 

B) State why group 0 elements have electron affinity value '0'.

C)  State the trend in density of elements on moving across a period and a down a group.

3) Supply the missing word from those given in the brackets:

Elements in the same group of the Periodic Table have ___ (different/same) number of Valence Electrons, while elements of the same period have____ (same/different) number of electron shells.

4) What happens to the electronegativity on moving down a group in the periodic table.

19/4/22

1) Write the balanced equations for each of the following reactions involving an oxide.

A) Lead(IV) oxide and concentrated hydrochloric acid.

B) Lead(II) oxide(heated) and ammonia.

C) Zinc oxide and dilute nitric acid.

D) Sodium oxide in sulphur dioxide.

E) Iron (III) oxide and Aluminium.

2) Define the following periodic properties.

A) Ionization potential.

B) electronegativity.

3) State the following pertaining to the Periodic Table.

A) The period of the Periodic Table which has two elements in its period.

B) the period to which the element carbon belongs.

C) the element in period 2 with the highest ionisation potential.

D) the Nobel gas present in period two of the Periodic Table.

4) Supply the missing word/s in the blanks below.

A) Sodium is an____ metal belonging to group___ of the periodic table. It has___ electron/s in its valence shell and is a strong_____ agent.

BIOLOGY (Revision) (X)

1) Name the gland which secretes insulin.

2) name the part of the brain which is concerned with memory.

3) Write the function in one word:

A) white blood cell

B) kidney 

C) myelin sheath

D) spinal cord

4)a) The blood vessel which carries oxygenated blood to the heart is ____(aorta, pulmonary vein, pulmonary artery)

b) Myopia can be corrected by __(convex lens, concave lens, surgery).

5) Difference between

cerebrum and cerebellum (function)

6) a) Presbyopia is generally an age related eye defect. T/F

b) Deafness is caused due to rupturing of the pinna. T/F

c) Over secretion of thyroxine causes simple goitre. T/F

7) one man function of

A) ear ossicles

B) Irish

C) pituitary gland

8) Odd one out

a) spleen, Thymus, pancreas, tonsil

9) difference between 

A) blood plasma and serum

B) neuron and nephron

C) night blindness and colour blindness

10) draw a diagram of the human excretory system and lebel the following:

 A) renal Cortex, renal medulla, renal pelvis, ureter, urinary bladder, urethra.

B) List the main constituent of normal human urine.

C) name the blood vessel which enter and leave the kidney.

11) Explain:

A) Abnormally large numbers of WBCs in the blood is usually an indication of some infection in our body.

B) veins have valves at intervals in their inner lining whereas the arteries do not have valves.

C) Insulin is injected into the body of a highly diabetic patient and not given orally.

PHYSICS (Revised) (X)

1) Explain the difference between natural and forced vibrations of a given object.

2) A student makes a 'parallel combination' of a given number of cells. Cite one advantage and one disadvantage of this arrangement.

3) An electric heater of wattage 2kW and two light bulbs, of 60 W each, are kept 'on' for 5 hours. Find the cost of the electricity consumed if each 'unit' of electricity costs ₹2.00. 21.20

4) Why are we advised not to use wet hands for 'putting off' a switch? 

5) What is the importance of a 'fuse' in an electric circuit ?

6) Of which physical quantity is the 'kWh' a measure ? Calculate the value of 1 kWh in joule.

7) Name the three wires used in domestic wiring systems.

8) A stretched string is being made to vibrate in its 'fundamental frequency ' mode. Give two factors on which this fundamental frequency, of the vibrating stretched string, depends.

9) Soldiers are adviced to march 'out of step' while crossing bridges.

10) It is desired to find out the specific heat capacity of brass experimentally. For this purpose, 0.2 kg of hot water, at an initial temperature of 65°C, is poured into a heavy brass container of mass 1.5 kg. The brass container is initially at 15°C and gets heated up to 45°C, after pouring the hot water and stirring it well. The specific heat capacity of water is 4200 J/kg/°C.

A) How much heat energy does the hot water give out when it cools from 65°C to 45°C ? 16800 J

B) If the heat energy, released by the hot water, is totally used by the brass container, in raising its temperature from 15°C to 45°C, find the heat energy absorbed by it per degree Celsius rise in its temperature. 560 J/°C

C) What is the specific heat capacity of brass? 373.3 J kg(°C)

11) During the radioactive decay, a radioactive nucleus decays either by emitting an alpha particle or Beta particle. In both cases, it also simultaneously emits gamma rays.

A) Compare the ionising power of gamma radiation with that of alpha and beta particles.

B) How does the penetrating power of gamma rays compare with that of alpha and beta particles.

C) Do gamma rays gets deflected by electric or magnetic fields in the same ways as alpha or gamma particles get ?

D) what is the nature of charge, if any, of gamma radiation?

 

12) The isotope ²²⁶Ra₈₈ is known to decays through the emission of Alpha particles.

A) Find the change in the atomic number of the Radium nucleus when it emits an Alpha particle.

B) find the change in the mass number of the radium nucleus when it emits an Alpha particles.

C) When ²²⁶Ra₈₈ emits Alpha particles, which of the following elements is likely to be formed:

Polonium (Po₈₄); Astatine (At₈₅); Radon(Rn₈₆); Francium (Fr ₈₇ ).

C) What is the nature of

  i) alpha rays

 ii) Beta rays

 iii) gamma rays.

AMMONIA

1) NAME THE FOLLOWING:

 

a) products obtained by burning Ammonia in Oxygen.

b) Gas obtained by treating chlorine in excess with ammonia.

c) solid obtained by passing Ammonia over heated copper oxide .

d) products obtained when a mixture of ammonia and oxygen is passed over heated Platinum.

e) Gas obtained by treating metallic nitrides with hot water.

f) substance used to dry Ammonia .

g) raw materials used in the laboratory preparation of ammonia.

h) product obtained by treating chlorine in excess of ammonia.

i) basic gas that is used as a refrigerant.

j) salt known as salt ammonia.

k) salt used to clean metal surfaces before soldering tinning, etc.

l) Salt used in dry cells.

m) ammonium salt used in the preparation of alume.

n) ammonium salt used in explosives.

o) products obtained by the catalytic oxidation of ammonia.

p) A gas which turns moist red litmus blue and reduces copper oxide to copper.

q) the gas evolved when calcium hydroxide and Ammonium chloride are heated.

r) A gas whose solution in water is alkaline.

s) a compound which on heating with Sodium Hydroxide produces a gas which forms dense white fumes with hydrogen chloride.

B) STATE WHETHER TRUE OR FALSE. ALSO CORRECT THE INCORRECT STATEMENTS:

a) Platinum is used as a catalyst in the manufacture of ammonia by Haber's process.

b) A solution of ammonia dissolve in water is called liquid ammonia.

c) In the laboratory preparation of ammonia, ammonia is collected by upward displacement of air.

d) In the manufacture of ammonia by Haber's process. the reactants nitrogen and hydrogen are taken in the ratio of 3:1 by volume.

e) concentrated sulphuric acid can be used as a drying agent for Ammonia gas.

f) ammonium Hydroxide reacts with iron sulphate to form reddish brown precipitate of iron Hydroxide.

g) Ammonia gas can be identified with its strong rotten eggs smell.

h) a mixture of Ammonium Nitrate and slaked lime is used in the laboratory preparation of ammonia.

i) all ammonium salts on heating decomposes to liberate ammonia gas.

C) GIVE REASONS:

a) ammonia is to present in sewage water.

b) Ammonia cannot be collected over Water.

c) aqueous solution of ammonia gives a pungent smell.

d) Ammonia solution is used as a laboratory reagent to identify metal ions.

e) Ammonia solution is used to remove oil and grease.

f) liquid ammonia used as refrigerant.

D) ANSWER THE FOLLOWINGS:

1) Ammonia gives dense white fumes with hydrogen chloride gas. Name another gas which also gives white fumes.

2) During laboratory preparation, how is ammonia dried and collected ?

3) How would you distinguish between Zn² and Pb² using ammonium Hydroxide solution?

4) How are the following conversations brought about ? Give equations?

a) Ammonium chloride to ammonia

b) Sodium hydroxide to ammonia.

5) How is liquor ammonia different from liquid ammonia?

6) The following reactions are carried out:

A: nitrogen+ metal-->compound X

B: X+ water--> ammonia+ another compound

C: ammonia+ metal oxide--> metal+ water+ nitrogen.

     One metal that can be used for reaction A is magnesium.

a) Write the formula of the compound X formed when nitrogen and magnesium react together.

b) Write the correctly balanced equation for reaction B where X is the compound formed between nitrogen and magnesium.

c) What property of ammonia is demonstrated by reaction C?

7) Industrially ammonia is obtained by direct combination between nitrogen and hydrogen.

a) write the correctly balanced equation for the direct combination of Nitrogen with hydrogen.

b) which of the metal, Iron, Platinum or copper catalyze this direct combination?

c) is the formation of ammonia promoted by the use of high pressure or low pressure ?

8)a) is ammonia more than dense or less dense than air? 

b) what property ammonia is demonstrated by the fountain experiment ?

c) write the correctly balanced equation for the reaction between Ammonia and sulphuric acid.

9)a) which feature of ammonia molecule leads to the formation of the ammonia dissolves in water?

b) name the other Ion formed when Ammonia dissolve in water.

c) Give one test that can be used to detect the presence of the ion produced in (b).

10)a) Of two gases, Ammonia and hydrogen chloride, which is more dense ? Name the method of collection of the gas ?

b) give one example of a reaction between the above two gases which produces a solid compound.

11)a) what is the purpose of the Haber's process ?

b) name the gaseous inputs of the Haber's process and state the ratio by volume in which the gases are mixed.

c) what is done to increase the rate of a reaction in Haber's process ?

d) give two different ways by which the product can be separated from the reactants.

12)a) how soluble is ammonia in water ?

b) give two reasons to show that the solution of ammonia in water contains contains hydroxide ions.

c) Name a simple method you would employ to prepare ammonium salts in your laboratory.

E) OBSERVATION QUESTIONS:

1) when water is poured over aluminium nitride (AIN)?

2) when ammonia is bubbled through red litmus solution?

3) when a piece of moist red litmus paper is placed in a glass jar of ammonia.

F) BALANCE THE FOLLOWING:

 

1) 2NH₄Cl + Ca(OH) ₂ --> CaCl₂ + 2H₂O + 2NH₃ .

2) ammonium chloride and sodium hydroxide are heated.

3) chlorine with excess of ammonia

4) Ammonia sulphate from ammonia and dilute sulphuric acid.

5) NH₃+ Cl₂--> ____+ ______

6) 2NH₄OH(aq) + H₂SO₄ --> ___+ ___

7) 8NH₃+ 3Cl₂--> ____+____

8) CuO + NH₃-->___+___+____

9) 4NH₃+ 5H₂O --> ___+_____

G) Select from the list given below (A to F). The one substance which matches the given description.

A. Ammonia

B. Copper oxide

C. Copper sulphate

D. Hydrogen chloride

E. Hydrogen sulphide

F. Lead bromide

Although this compound is not a metal hydroxide, its aqueous solution is alkaline in nature.

H) FILL IN THE BLANKS:

1) Ammonia chloride is a soluble salt prepared by ______ (precipitation/neutralization)

2) When Ammonium chloride is heated, it undergoes thermal____. (Decomposition/dissociation)

3) Heating Ammonium chloride with sodium hydroxide produces ___.(ammonia/nitrogen).

PRESSURE IN FLUIDS

1) Write the characteristics of pressure in fluids.

2) Define:

a) Pascal's Law.

b) Atmospheric pressure

c) Barometer

3) Name the factors which affect barometric height.

4) Name the factors which do not affect barometric height.

5) State three factors which determine the pressure of a fluid at a given point within the fluid.

6) Pressure in case of solids is inversely proportional to area of cross section. Does the above statement hold for a fluids?  Explain your answer.

7) REASON:

a) Pressure of water on the first floor building is always less than pressure of water at the ground floor.

b) water tank in a locality is always at higher altitudes than building in the locality.

c) Sense of hearing is affected while rapidly gaining or losing height.

d) The nose of some people stars bleeding when an aeroplane climbs up rapidly.

e) A soda straw does not draw liquid, if there is a tiny hole near its upper end.

f) why do the bodies of deep sea fishes burst, on bringing them above the sea level?

g) Why does an ink pen start leaking at higher altitudes?

h) Why are special suits worn by astronauts while floating in space ?

i) why you are weather observation balloons filled partially with helium gas at ground level ?

j) why are two holes made in oil tin, to remove oil from it ?

k) why does not liquid run out of a dropper, unless rubber bulb is pressed ?

8) a) what unit does Pascal measure ?

b) State the law of transmission of pressure in liquids

c) A cylinder contains water up to the height of 40cm. If the density of water is 1000 kgm³ and acceleration due to gravity is 9.8 m/s². Calculate the hydrostatic pressure exerted by water at the bottom of cylinder on its sides.

9) a) state whether the pressure acting at a point in a liquid is a scalar quantity or vector quantity.

b) a glass container contains a liquid of density P, when the height of liquid is H and acceleration due to gravity is G. If P' is the atmospheric pressure, calculate 

     i) the pressure on the free surface of the liquid.

    ii) the total pressure at the base of container.

   iii) what is the magnitude of lateral pressure at the base of liquid, on the inner side of container?

10) How does the fluid pressure on a balloon changes when:

a) balloon rises up from height of 200m to a height of 500m ?

b) balloon move horizontally at a height 200m ?

c) balloon is a brought down on the surface of earth ?

11) FILL IN THE BLANKS:

a) the pressure of the sea water for same depth is ___ than the river water (less/more)

b) The pressure of air ____as we move upward. (increases/ decreases)

c) The fluids exert ___pressure in all directions at a given point. (different/same)

d) The fluid pressure of liquid increases with increase in ____(depth/area of cross section)

e) the fluid pressure of atmosphere is measured in ____. This is equivalent to___ Pascals

12) State any two uses of hydraulic press.

13)a) what do you understand by the term atmospheric pressure 

b) What is the cause of atmospheric pressure ?

c) State the numerical value of atmospheric pressure at sea level in 

  i) cm of Mercury 

  ii) Pascals

  iii)  bars 

14) a) Name the instrument used for measuring the atmospheric pressure.

b) How will you set up such an instrument in a laboratory ?

c) State the precaution for the use of this instrument?

15) Explain the following 

a) Why is water not a suitable barometric liquid ?

b) Why is mercury used as a baromatric liquid?

c) Name two factors which do not affect barometric height on a given place?

d) name four factors which affect barometric height at a given place.

16) a) Draw a neat fully labelled diagram of aneroid barometer.

b) Explain how aneroid barometer is used for.

       i) Forecasting weather 

      ii) as an altimeter

17) State the forecast in the following situations.

a) air in hot and dry and atmospheric pressure falls suddenly.

b) air is humid and barometric pressure falls suddenly.

c) barometric pressure rises steeply.

d) barometric pressure does not change.

e) Barometric pressure falls gradually over number of days.

SOUND(IX)

 

1. Sound : It is a mechanical energy which produces sensation of hearing.

2. Condition for the propagation of sound:

  i) There must be vibrating body, carable of transferring energy.

  ii) There must be a material medium, through which energy can propogate.

 iii) There must be receiver(ear), so as to receive and transmit energy to brain.

3. Infra-sonic or sub-sonic vibrations : The vibration which are not perceived by human ear and have a range 0-20 Hz are called infra-sonic vibrations.

4. Sonic-vibrations:  The vibration which produce sensation of hearing in human beings are called Sonic vibrations . Their range is between 20- 20000 Hz.

5. Ultra-sonic vibrations : The vibrations which are not perceived by human ear and their frequency range is above 20000 Hz are called ultra-sonic vibrations .

6. Bats navigate by emitting ultra-sonic vibrations and then receiving the echoes . Dogs and dolphins can also heer ultra-sonic vibrations .

7. Ultra-sonic vibrations are used in 

i) homogenising milk and cosmetics.

ii) in dissipating fog.

iii) in dish cleaner 

iv) Ultra-sound welding

v)  ultra-sound scanning of human body.

8) Elastic waves:  The waves produced in a material medium are called....

9) Transverse waves: When the particles of a medium vibrate at right angles to the direction of propagation of wave, then the wave so produced is called,...

10) Longitudinal wave: When the particles of a medium vibrate in the same direction in which a wave propagates , then such a wave is called....

11) Transverse wave is possible in solids only, whereas Longitudinal wave is possible in all kinds of material medium.

12) As a general rule, sound travels faster than solids, slower in liquids and slowest in gases.

13. The speed of the sound in solids and liquids at constant temperature is 

i) directly proportional to square root of elasticity 

ii) inversely proportional to square root of density of material.

14) The speed of sound in gases at constant temperature is given by v= √{γP/d}, where γ = 1.414; 'P' is the pressure of a gas and 'd' is the density of gas.

15) Speed of sound in air does not change with the change in

i) frequency 

ii) wavelength 

iii) amplitude 

iv) pressure.

16. Speed of sound in air increases by 0.6 m/s for every 1°C rise in temperature.

17) Speed of sound in air increases with the increase in humidity and vice versa.

18) Speed of sound in air decreases with increase in density and vise versa.

19) Speed of sound in air increases if the direction of sound and wind are in same direction and vise versa.

20) Wave: The disturbance produced in a medium by the to and fro motion of its particles about their mean position is called...

21) Wave motion: The transfer of energy when the particles of a medium move about their mean positions is called wave motion.

22) Material wave or elastic waves: The waves produced in a material medium (solids; liquid or gases) by the movement of its particles about their mean positions are called material waves or elastic waves.

23) Characteristics of material medium for the propagation of sound:

i) it must be elastic.

ii) It must have least frictional resistance.

iii) It must possess inertia.

24) Amplitude: The maximum displacement of a particle about its mea position is called amplitude.

25) Frequency(f): The number of vibrations executed by a particle of a vibrating medium about its mean position in one second is called frequency.

OR

The number of waves passing through one particular point in one second is called the frequency.

26) Time period or periodic time (T): The time taken to complete one oscillation by any particle of a vibrating medium is called.....

27) Phase: The term used to describe the motion and direction of a vibrating particle, at some particular instant, during its course of motion is called phase .

28) Same phase: When two particles are moving exactly in the same way i.e., their displacement from mean position is same and so is direction, they are said to be in the same phase.

29) Opposite phase: When two particles are moving exactly in opposite way i.e., their displacement from mean position is same, but direction is opposite, they are said to be in opposite phase .

30) Out of phase: When the motion of the two particles in a vibrating medium is not similar in any respect, they are said to be out of phase.

31) Wave velocity (v): The distance covered by a disturbance in one second in some particular direction is called ...

32) Wavelength (λ): The linear distance between two consecutive particles of vibrating medium in the same phase is called....

OR

Linear distance covered by one complete wave is called....

QUESTIONS 

1) State three conditions necessary for hearing sound sound.

2) Describe briefly an experiment to prove that vibrating bodies produce sound.

3) Name three animals which can hear ultra-sonic vibrations .

4) How do bats locate their prey during flight ?

5) What is Galton's whistle ? To what use it can be put ?

6) State four practical uses of ultra-sonic vibrations .

7) Describe an experiment to prove that material medium is necessary for the propagation of sound.

8) Why do the astronauts talk to each other through radio telephone in space or on the surface of moon?

9)  What are electric waves ? Name two kinds of elastic waves.

10) Define the term longitudinal wave and show it diagrammatically.

11)  State four characteristics of the longitududinal waves.

Characteristics:

12) Define the term transverse wave and show it by diagram.

13) State for characteristics of the transverse waves .

14) With reference to sound. which amongst the longitudinal wave and transverse wave is possible in a) solid  b) gases ?

15) State four differences between longitudinal wave and transverse wave.

 they consist of regions of compressions and rarefaction.

16) State three factors which determine the speed of sound in a material.

17) State the formula of speed of sound in solids.

18) State the formula of speed of sound in gases.

19) Amongst the air, carbon dioxide and helium, state in which material speed of sound is 

a) Maximum 

b) Minimum and why?

 20) How is the speed of sound in air affected when the following parameters chang?

a) wavelength of sound wave increases.

b) pressure of air increases 

c) temperature of air falls.

d) humidity in air increases.

e) Amplitude of sound wave decreases

f) the wind blows in the direction opposite to the direction of propagation of sound.

g) frequency of sound wave decreases.

h) The density of air increases, without any change in pressure.

21) How do the following affect, at all, the velocity of sound in air ?

a) pitch of sound 

b) temperature of air

c) pressure of air.

d) moisture in air.

22) Give one example of longitudinal and transverse waves

23) The sound of an explosion on the surface of lake is heard by a boatman 100 m away and a driver 100 m below the point of explosion.

a) Of the two persons mentioned (boatman and diver), who would hear the sound first?

b) Give reason for your answer in (a).

c) If the sound takes 't' seconds to reach the boatman, approximately how much time it will take to reach the diver ?

24) State the important difference between light and sound waves.

25)) What is approximate value of the speed of sound in iron as compared to that in air ? Illustrate your answer with simple experiment.

26) How does a bat avoid obstacles in their way when in flight ?

27) A continuous disturbance is created on the surface of water in a ripple tank with a small piece of cork floating on it. Describe the motion of cork.  What does motion of cork tell about disturbance .

28) Draw a displacement-time graph for water wave.

29) State any two characteristic of wave motion.

30) State three main characteristics of medium necessary for the propagation of sound waves.

31) Derive a relation between frequency and time period.

32) Derive a relation between wave velocity; frequency and wavelength.

33) The diagram shows a snap shot of a wave form of frequency 50Hz on a string. The numbers in diagram represent distance in centimetres.

 For this wave motion find

a) Wavelength 

b) Amplitude 

c) wave velocity.

34) Draw a diagram representing a wave of 

a) amplitude 4cm

b) wavelength 2m. if the frequency of wave is 150 Hz, calculate its velocity.   300ms⁻¹ 

35) The diagram shows a vibrating metal blade clamped at one end. P and R are the extreme positions occupied by the blade during its course of vibration. Q,  being its position of rest. The vibrating blade produces a note of 480 Hz.

i) Mark the diagram amplitude of vibration.

ii) if the velocity of the sound in air is 320 ms⁻¹, what is the wavelength of sound produced ?      0.66 m

36) Explain why lightning flash is seen before the crack of thunder.

NUMERICAL PROBLEMS

1) The speed of the sound at 4° C is 322.4 ms⁻¹. Calculate the speed of sound at 34° C.       340.4 ms⁻¹

2) The speed of sound at -5°C is 317ms⁻¹. Calculate the speed of sound at

a) 35°C.    341ms⁻¹

b) - 45° C.   293 ms⁻¹

3) The speed of sound at 0° C is 320 ms⁻¹. Calculate the temperature when speed of sound

a) increases by 1/8th of speed of sound at 0°C.   66.67°C

b) decreases by 1/12th of speed of sound at 0°C.       -44.45°C

4)  The speed of sound at 10°C is 326 ms⁻¹. Calculate the temperature at which speed of sound is 302ms⁻¹.     -30°C

5) A sound wave of frequency 640 Hz travels 800 m in 2.5s. Calculate 

a) speed of sound.     320ms⁻¹

b) wavelength of sound wave.     0.5m

6) A television station broadcasts at a frequency of 4500 MHz. If the speed of television waves is 3 x 10⁸ ms⁻¹. Calculate the wavelength of television waves.     0.067 m

7) A longitudinal wave of wavelength 0.03 cm travels in air with a speed of 330ms⁻¹.

Calculate the frequency of the wave. Can this wave be heard by normal human ear. Give a reason for your answer.         1100000 Hz, The above wave cannot be heard. It is because, the maximum range to which human ear can hear is 20000 Hz. As the frequency of 1100000 Hz is far in excess thereore it will not produce any sound effect in ear.

8)  a sound wave as a frequency of 2000 wavelength 17 if the wavelength increases by 51 what is the frequency the nature of the material through which sound is propagation remains of 22 a disturbance in here as were length of 22 and speed calculate the frequency of disturbance state whether they were disturbance is audible normal human ear give one reason for your answer ultraviolet radiation is wavelength 150 + the ultraviolet radiation is 3 calculate the frequency of radiation time period the web length of the waves produced on the surface of the water is 20 the way velocity is 24 calculate the number of produced in 1 second time required to produce one web ET metal plate is placed again if the cogil is rotted at a constant speed of 360 rotation per minute calculate the frequency of a note produce speed of the sound if the wavelength 0.7 what will be the refractive the speed of the cow will be hacked in turning for can produce a lot of problem 0.83 and has a time period of 2.5 into 10 seconds calculate the web velocity the distance between 1 crest and one trap produce on the surface of water is 0.04 if the waves are produced at the rate of 184 M calculate time period and web velocity

A) Fill the blanks:

1) Sound is produced due to the-- in the medium

2) Sound requires a -- to travel.

3) Bats detect obstacles in their path by receiving the reflected...

4) The note of the lowest frequency for a vibrating string is called....

5) Quality of sound depends upon.. frequencies.

6) To hear the echo of a sound, the reflecting surface should be at a minimum distance of---

7) The pitch of sound .... if the frequency is increased.

8) The Intensity of sound is ....to the square of the amplitude of wave.

9) The sound becomes... if amplitude is increased.

10) Resonance is a special case of... vibrations, when frequency of the driving force is ...to the natural frequency of the body.

B) State whether True/False. Also correct the false statements.

1) The sound heard after reflection from a rigid obstacles is called an echo.

2) Resonance occurs when natural frequency of a body is less than the frequency of the applied force.

3) The vibration of a body with constant amplitude and constant frequency are called forced vibrations.

4) The frequency of vibrations of air column is directly proportional to the length of the air column.

5) The loudness is a measurable quantity while intensity is a sensation.

6) The pitch of sound increases if it's frequency increases.

C) Answer the following

1) a) Define echo.

  b) State two conditions necessary 

       for an echo.

  c) Write its use.

2) What is vibrated to produce sound in :

a) a violin

b) an organ pipe

c) a drum

3) Define:

a) Free vibrations of a body ?

b) Forced vibrations?

4) Define Resonance. State the condition necessity for resonance to occur.

5) State the physical quantity whose unit is decibel. Name another unit of this physical quantity.

6) Are intensity and loudness the same ?

7) Name three characteristics of a musical sound.

8) What determines the pitch of a sound ?

9) State one factor that determines the quality of a musical note.

10) a)What is Sonar ? 

b) State the principle on which it is bases .

c) State its uses.

11) Write a relation between the velocity of sound and distance of source of sound from reflecting body and time for hearing an echo.

12) Name the subjective Property of sound related to its frequency.

13) Give one example each of

a) Natural vibration

b) Forced vibration

c) Resonance

14) A turning fork held over an air column of a given length, produces a distinct audible sound. What do you call this phenomenon? How does it occur ?

15) How can one distinguish the sound of two musical instruments even if they are of the same pitch and the same loudness ?

16) How is the speed of sound in air affected when the following parameters change?

A) Wavelength of sound wave increases

B) Pressure of air increases

C) Temperature of air falls

D) Humidity of sound wave increases

E) Amplitude of sound wave decreases

F) Frequency of sound wave decreases

17) What change, if any, would you expect in the characteristics of a musical sound when we increase

A) Its frequency

B) Its amplitude

REASON BEHIND:

1) The rear view mirror of a motor bike starts vibrating violently at some particular speed of the motor bike.

A) Why does this happen?

B) What is the name of the phenomenon taking place?

C) What could be done to stop the violent vibrations?

2)A) How does a stretched string on being set into vibration, produce an audible sound?

B) will this sound be audible if the string is set into vibration on the surface of the moon? Give reason for your answer?

3) Women's voice is shriller than men's voice.

4) Why lightening flash is seen before thunder is hard ?

5) why are the stringed instruments provided with a sound box?

6) Why is bell provided with a big outer case?

7) Two friends were playing on their identical guitars whose strings were adjusted to give notes of the same pitch. Will the quality of the two notes by the same? Give a reason for your answer?

8) We can recognise our friends even by listening to their voices.

9) A renowned singer's voice is sweeter.

10) It is not possible to talk through an open space.

11) How a megaphone can help in making the sound heard at a distance OR Why do we cup our hands to make the sound heard at a distance.

12) Windows sometimes rattle when the low notes of pipe organ are sounded.

13) Tick, Tick of watch is not musical while buzzing of a bee is.

14) Why is a loud sound head at acoustic resonance

15) Why echo can't be heard in a small room

16) Why can we hear echoes in long galleries and big halls?

17) Bat have no eyes still they can ascertain distances, directions nature and size of the object.

18) Why soldiers asked to walk out of step while crossing bridges

19) How does frequency and amplitude affect a musical sound?

20) Why strings of different thickness are provided on a stringed instrument.

21) A vibrating turning fork is placed over the mouth of a burette filled with water, the tap is opened and the water level gradually falls. It is observed that the sound becomes the louder for a particular length of air column.

A) What is the name of the phenomenon taking place when this happens?

B) Why does the sound become the loudest?

C) What is the name of the phenomenon taking place when sound is produced for another length of air column and is not loudest?

DIFFERENCE BETWEEN

A) Musical note/Noise

B) Resonance/Forced vibrations

C) Free vibrations/Forced vibrations

Health, Diseases and Hygiene

1) DEFINATION:

a) Acquired diseases.

b) Allergy.

c) Antibody.

d) Antigen.

e) Antitoxin.

f) Asymptomatic carrier.

g) Carrier.

h) Communicable diseases.

i) congenital disease.

j) Conjunctivitis.

k) Deficiency disease.

l) Degenerative disease.

m) Disease.

n) Droplet infection.

o) Epidemiology.

p) Germ theory of disease.

q) Health. 

r) Hygiene.

s) Immune system.

t) Immunization.

u) Incubation period.

v) Infection.

w) Infectious disease.

x) Lock jaw 

y) Non-communicable disease.

z) Social hygiene.

a') Transplancental transmission.

b') Trachoma.

c') Vaccine.

d') Vector.

 

2) List the causative factors of diseases. 

3) Differentiate between infectious and noninfectious diseases.

4) Explain the different type of non infectious diseases giving one example of each type.

5) List the different ways by which disease are transmitted.

6) What are pathogens? How do these cause diseases in human beings ?

7) List three diseases caused by each of the following microorganisms.

a) Viruses.

b) Bacteria.

c) Protozoans.

d) Worms.

8) List the symptoms and the preventive measures of the following diseases:

a) Mumps.

b) Chickenpox.

c) Tuberculosis.

d) Cholera.

e) Filaria.

9) What is DPT Vaccine ? What for is it given to the children ?

10) How do the following diseases spread ?

a) Cholera.

b) Influenza.

c) Tuberculosis.

d) Taeniasis.

11) Name the diseases caused by the following:

a) By mites.

b) By fungi 

c) By insect-bite.

12) Explain how do each of the following animals spread the diseases and how they can be controlled .

a) Housefly 

b) Rats.

c) Mosquito.

d) Cockroaches.

13) Personal cleanliness and cleanliness of the surroundings are important to good health. Give reasons.

14) What is the importance of keeping hair, teeth and finger nails clean ? How would you keep them clean ?

15) What steps whould you undertaken to maintain social hygiene ?