Question

determination of focal length of concave lens for practicals​

Answer 1

Explanation:

To determine focal length of a given concave mirror

To determine focal length of a given concave mirrorTo obtain a clear, sharp image the screen should be adjusted. Using a metre scale the distance between the concave mirror and screen can be determined. The distance is the same as the focal length of the given concave mirror.

Answer 2

Answer:

Place the screen in front of the reflecting surface of the mirror. Move the screen back and forth until a clear, sharp image of the distant object is obtained on the screen. Measure the distance between the concave mirror and the screen with a metre scale. This distance is the focal length of the given concave mirror.