Question

A converging lens has a focal length of 0.05 m. If an object is placed at 0.76 m from the lens, where will its image be located?

Is it real or virtual?

Answer 1

Solution. Using the lens formula

$$\frac{1}{f}=\frac{1}{u}+\frac{1}{v}$$

where f=0.05m is a focal length; u=0.76m is object distance; v is image distance. Therefore

$$v=\frac{fu}{u-f}=\frac{0.05\times 0.76}{0.76-0.05}\approx 0.054m$$

Received image are real, reduced, and inverted

Answer. 0.054 m, real.