10th Class Physics MCQS Chapter 3

Speed of light in air is ms ¹

3 x 10¹¹

3 x 10⁸

3 x 10⁵

340

Concave mirror formula is given by:

sin<i/sin<r

1/f=1/p+1/q

R = 2r

1/f=1/p 1/q

An object of placed at he centre of curvature of a concave mirror. The image produced by the mirror is located:

at the centre of curvature

out beyond the centre of curvature.

at the focal point

between the centre of curvature and the focal point

Power of convex lens is 10 D. Its focal length is:

1 m

10 m

0.1 m

100 m

Optical fibers work on the principle of:

Total internal reflection

Reflection

Refraction

Diffraction

Hard disk is made of:

Plastic

Copper

Aluminium

Iron

The minimum value of angle of deviation is called:

Minimum angle

incident angle

angle of minimum deviation

None of these

The ray of light striking to the side of prism is called:

refraction ray

incident ray

emergent ray

reflected ray

Optical fibre are:

Cheap

Lighter

All of these

Flexible

The refractive index of internal coating of optical fibre is:

1.56

1.53

1.51

1.58