# One method of measuring the focal length of a lens is to form an image of an object that is many focal lengths away from the lens. Show from equation (1/f=1/o+1/i)  that the image distance is approximately equal to the focal length when the object distance is very large (say, o=100f). What happens when the object distance become infinitely far away?

Question
33 views

One method of measuring the focal length of a lens is to form an image of an object that is many focal lengths away from the lens. Show from equation (1/f=1/o+1/i)  that the image distance is approximately equal to the focal length when the object distance is very large (say, o=100f). What happens when the object distance become infinitely far away?

check_circle

Step 1

The given expression from lens formula,

Step 2

Substitute the values,

Step 3

If the object distance become infinity, the inverse of object distance will be zero.

Thus, from ...

### Want to see the full answer?

See Solution

#### Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in