Question

How would you determine the focal length of a concave mirror experimentally?​

Answer 1

Procedure for following above experiment:-

Without disturbing the lens and screen, arrange both of them on the wooden bench.

Place the lens on the holder facing a distant object.

Place the holder with the screen on the bench.

The position of the screen should be such that the sharp image of the distant object is obtained on it.

The difference between the position of the lens and the screen is equal to the focal length of the given convex lens.

Now shift the focus to towards various other distant object and calculate the focal length of the convex lens.

Hope this helps you...!

Answer 2

Place the holder with the screen on the bench. The position of the screen should be such that the sharp image of the distant object is obtained on it. The difference between the position of the lens and the screen is equal to the focal length of the given convex lens.