Question

A 4.5cm needle is placed 12cm away from a convex mirror of focal length 15cm. Give the location of the image and the magnification. Describe what as the needle if moved farther from the mirror.

Answer 1

The image will be formed 6.66cm behind the mirror according to mirror formula

1÷15=1÷v-1÷12

m=-v÷u=6.66÷12

As the needle is moved farther the image will be formed closer to the mirror behind it.