An object with a height of 60cm is placed at a distance of 60cm from the collecting lens with a focal length of 12cm.

An object with a height of 60cm is placed at a distance of 60cm from the collecting lens with a focal length of 12cm. determine at what distance from the lens the image was obtained and the size of the resulting image.

Let’s use the formula for the focal length of the converging lens and find the distance f:

1 / F = 1 / f + 1 / d → f = (d * F) / (d – F) = 0.15 m = 15 cm.

Let’s write down the proportion to enlarge the lens and find the size of the resulting image H:

f / d = H / h → H = f * h / d = 15 * 60/60 = 15 cm.

Answer: 15 cm.