Section – II
PHYSICS
Q). A person is not feeling hot or cold with surroundings. Then he is in the state of
A) thermal equilibrium
B) high temperature
C) low temperature
D) both high and low temperatures
Q). x g of water is heated from y°C to z°C. The quantity of heat required in calories is
A) X(y/z)
B) X(z/y)
C) X(Z-y)
D) X(z+y)
Q). During phase change of a substance
A) temperature remains constant
B) temperature increases
C) temperature decreases
D) temperature may increase or decrease
Q). When parallel rays are incident on a concave mirror, at what point do they meet after reflection?
A) Centre of curvature
B) Focus
C) Pole
D) Infinity
Q). Which of the following relations is correct in general for spherical mirrors with object distance u, image distance v and focal length f?
A) -1/f =1/u+1/v
B) 1/f =1/u+1/v
C) 1/f =1/u x 1/v
D) 1/f x 1/u =1/v
Q). An object is placed between pole and focus of a concave mirror. The nature of the image is
A) real, inverted and diminished
B) real, inverted and same size
C) virtual, erect and enlarged
D) virtual,- erect and diminished
Q). If speed of light in medium 1 is V1 and in medium 2 is v2, then the refractive index of second medium with respect to first medium is
A) n 12 =v 1 /v 2
B) n 21 = v 2 / v 1
C) n 21 = v 1 / v 2
D) n 12 =v 2 /v 1
Q). The main principle behind working of optical fibers is
A) total internal reflection
B) dispersion
C) refraction
D) reflection
Q). The formula for refractive index (n) of a prism having angle of prism A and angle of minimum deviation D is
A) n = 
B) n = 
C) n = 
D) n = 
Q). What happens to refractive index of a medium when wavelength of incident light ray increases?
A) Decreases
B) Increases
C) Becomes zero
D) Becomes infinity
Good