Question

The diameter of the moon is about 3500 km. What will be the size of the image made of the Moon by a concave mirror whose radius is 3m when the nearest distance from Earth to the Moon is 35 x 10 to the power 4 km.​

Answer 1

Explanation:

Here, angle subtended by moon

=

3⋅5×10

5

3500

radians

Also, focal length of the mirror,

f=R/2=1⋅5m

=1⋅5×10

3

mm

Required diameter of image

∴D=fθ=1⋅5×10

3

×

3⋅5×10

5

3500

=15mm