Question

A concave mirror of focal length 10cm has been broken into pieces .do we observe any change in focal length​

Answer 1

Answer:

No, a change will not be observed.

Explanation:

1. When a concave mirror is broken, its center of curvature does not change because that piece was still part of a bigger sphere.

2. As the center of curvature does not change, the focal length, which is half of C does not change as well.

Answer 2

The correct answer is A.

Given,

A concave mirror

u=−10cm

f=10cm

So, By the mirror formula,

1/f = 1/u + 1/v

1/10 = -1/10 + 1/v

v=5cm

Now, magnification = - v/u = 5/10 = 1/2

So the length of the image in the upper part is:

h/2 = m

h/2 = 1/2= 1mm

Answer = 1mm