Question 1

Which of the following mirror can form a real, inverted, and magnified image?

Accepted Answer

A concave mirror can form a real, inverted, and magnified image when the object is placed between its focus (F) and center of curvature (C), or between the pole (P) and focus (F) for a virtual image. Therefore, option A is correct.

Question 2

The focal length of a spherical mirror is 20 cm. What is its radius of curvature?

Accepted Answer

The radius of curvature (R) of a spherical mirror is twice its focal length (f). Formula: R = 2f. Given f = 20 cm, so R = 2 20 = 40 cm. Therefore, option C is correct.

Question 3

When a ray of light travels from a rarer medium to a denser medium, it bends:

Accepted Answer

According to the laws of refraction, when light travels from an optically rarer medium (like air) to an optically denser medium (like glass or water), the refracted ray bends towards the normal. Therefore, option B is correct.

Question 4

The power of a lens is -2.5 D. What is its focal length?

Accepted Answer

Power of a lens (P) is given by P = 1 / f(in meters). Therefore, f = 1 / P = 1 / (-2.5) = -0.4 m, which is equal to -40 cm. Therefore, option A is correct.

Question 5

Which mirror is commonly used as a rear-view mirror in vehicles?

Accepted Answer

A convex mirror is used as a rear-view mirror in vehicles because it always gives an erect, diminished image and provides a wider field of view as they are curved outwards. Therefore, option B is correct.

Light – Reflection and Refraction