Question

19. The term evaporation refers to one of the forms for

(a) phase change
(b) magnetic transfer

(c) heat transfer
(d) none of the above

20. The amount of heat needed to increase the tem- perature of 1 gram of water by 1oC is called

(a) protein calorie (b) calorie

(c) BTU
(d) none of the above

21. The only type of heat transfer that can take place through vacuum is called

(a) convection (b) radiation

(c) conduction
(d) None. It’s impossible through vacuum

22. A change of amplitude of a light wave in the visible range is perceived by the brain as a change of

(a) brightness (b) phase

(c) color
(d) none of the above

23. The polarization is a wave property that applies to longitudinal waves

(a) true (b) false

(c) depends
(d) none of the above

26. The amount of heat absorbed or released when a

    substance undergoes a phase transition is called:

    (a) perfect heat (b) latent heat

    (c) equilibrium heat (d) thermal heat

27. A ball is moving at 6m/s and has a linear mo- mentum of 96kgm/s. What is the ball’s mass?

    (a) 4 kg (b) 12 kg (c) 16 kg

    (d) 144 kg

28. On the ultrasound scan of a patient, the scanning frequency is important because it affects

    (a) the eye of the patient
    (b) the temperature of the patient

    (c) the resolution of the image (d) none of the above

29. The apparent change of frequency when the source is approaching or receding is called

    (a) Einstein effect (b) Dornier effect (c) Doppler effect

    (d) none of the above

30. What type of wave is the electromagnetic radia- tion in the radio range?

    (a) transverse (b) longitudinal

    (c) not a wave (d) none of these

31. The gamma rays can propagate in vacuum?

    (a) yes (b) no

    (c) light is not a wave (d) none of the above

Answer 1

19.Option A is the answer.Evaporation is the conversion of a liquid to its vapour below the boiling temperature of liquid.That is it refers to a phase change from liquid to vapour.

20.Option D is the answer.The amount of heat required to raise the temperature of 1g of water by 1 degree celsius is called specific heat capacity of water.

21.Option B is the answer .Radiation doesnot requires a material medium.So it takes place through vaccum.

22.Option A is the answer.Amplitude of the wave is associated with brightness or intensity.Larger amplitude have high brightness.

23.Option B is the answer.Polarization is a wave property that applies only to transverse waves.Longitudinal waves can't be polarized because its particles vibrate in the same direction that the wave travels.

24.Option B is the answer.The quantity of heat absorbed or released when a unit mass of substance undergoes phase change is called latent heat.

25.We know that Momentum ,P= mass ×velocity

Therefore , Mass = P/V=96/6=16kg

So Option C is the answer.

26.Option C is the answer.Scanning frequency affects the resolution of the image.

27.Option C is the answer.Doppler effect is the apparent change in frequency when the source is approaching or receding.

28.Option A is the answer.Electromagnetic radiations are transverse waves.Its oscillations are perpendicular to the direction of travel of the wave.

29.Option A is the answer.Gamma rays can propagate through vaccum because it is an electromagnetic wave like light.