Question

3) a) A glass prism placed in a homogeneous transparent medium will deviate a light ray

A) always towards its base

B) always away from tis base

C) towards its base only if the medium has a refractive index smaller than that of glass

D) towards its base only if the medium has a refractive index greater than that of glass.

b) A convex lens forms virtual, erect and magnified image when the object is at

A) at centre of curvature (2F)

B) Between focal point and lens

C) between focal point and the centre of curvature(2F)

D) beyond centre of curvature(2F)

c) Two convex lenses of focal length 0.3m and 0.05m are used to make a telescope. The distance kept between them is equal to

A) 0.35m

B) 0.25m

C) 0.175m

D) 0.15m

d) Point out the wrong statement: Electromagnetic waves are

A) transverse

B) produced by accelerating charges

C) travel with the same speed in all media

D) travel with speed of light in free space

e ) When a pure semiconductor is heated

A) number of electrons increases while that of holes decreases

B) number of electrons decrease while that of holes increases

C) number of electrons and holes increase equally

D) number of electrons and holes remain the same

please show all calculations and clear explanation

Answer 1