set 11 MCQ Questions & Answers Detailed Explanation

Question : 1

‘The stars seem to be higher on the sky than they actually are’. This can be explained by

a) total internal reflection

b) atmospheric refraction

c) dispersion of light

d) diffraction of light

Question : 2

To keep drinks at the same temperature for quite sometime, the walls of thermos bottle are coated with

a) Lead Powder

b) Silver Layer

c) Aluminium Paint

d) Mercury Layer

Question : 3

Human eye is most sensitive to visible light of the wavelength

a) 4500 Å

b) 5500 Å

c) 6050 Å

d) 7500 Å

Question : 4

What is the function of the thermostat of a refrigerator?

a) To increase the freezing point

b) To maintain constant temperature

c) To lower the temperature

d) To decrease the melting point

Question : 5

A : At high altitude regions the cooking of food becomes difficult. B : Water boils at lower temperature when the pressure is low.

a) A and B are correct and B is the correct explanation of A.

b) Both A and B are wrong.

c) A and B are correct and B is not the correct explanation of A.

d) A is correct but B is wrong.

Question : 6

A sound wave having certain frequency is incident on air-water surface. A part of it is reflected and other part is refracted into water. Then:

a) the frequency of reflected wave will be more than frequency of refracted wave

b) the reflected wave will travel faster than refracted wave

c) the wavelength of refracted wave will be more than wavelength of reflected wave

d) the frequency, wavelength and velocity of reflected and refracted waves will be same as that of incident wave