Question

Describe a method to measure the focal length of a convex lens ?​

Answer 1

• Stand with your back to the sun. Hold the lens so the sun shines through it and onto a sheet of paper. Move the lens towards and away from the paper until the dot of light is focused. The distance from the center of the lens to the surface of the paper is the focal length.

Answer 2

Answer:

Stand with your back to the sun. Hold the lens so the sun shines through it and onto a sheet of paper. Move the lens towards and away from the paper until the dot of light is focused. The distance from the center of the lens to the surface of the paper is the focal length.