Question

You photograph a 2.0-m-tall person with a camera that has a 5.0 cm-focal length lens. The image on the film must be no more than 2.0 cm high.

(a) What is the closest distance the person can stand to the lens?
(b) For this distance, what should be the distance from the lens to the film?

Answer 1

To determine the closest distance the person can stand to the lens, we can use the lens formula. Given that the person's image must be no more than 2.0 cm high, we can use the magnification formula. By rearranging these formulas and substituting the given values, we can find the closest distance the person can stand to the lens and the distance from the lens to the film.

Step-by-step explanation:

To determine the closest distance the person can stand to the lens, we can use the lens formula:

1/f = 1/di + 1/do

where f is the focal length of the lens, di is the distance from the lens to the image, and do is the distance from the lens to the object.

Given that the person's image must be no more than 2.0 cm high, we can use the magnification formula:

m = -di/do

By rearranging these formulas and substituting the given values, we can find the closest distance the person can stand to the lens and the distance from the lens to the film.

(a) The closest distance the person can stand to the lens is approximately 83.33 cm.

(b) For this distance, the distance from the lens to the film should be approximately 7.5 cm.