Question

how could you find the focul length of a convex lens rapidly but approximately??​

Answer 1

Answer:

Explanation:

Put a paper and put the lens in front of it and capture the image of a distant object by moving the lens to and fro. When a sharp and inverted image is formed, measure the distance between the lens and the paper. That is a rapid and approximate method of measuring the focal length of the lens. Since u the distance from the object to the lens is large, 1/u can be neglected and that equation can be written as 1/v = 1/f and thus v = f ....

Hope it helps you

Answer 2

Answer:

1/u -1/v =1/f

1/v =1/f

v=f