Question

If radius of curvature of a concave mirror is 20cm and an object of height 3 cm is placed

at 30cm from the mirror. Find position, nature and size of the image?​

Answer 1

Answer:

position = image will be formed at the distance of 15 cm on the side of the object.

nature= 1.Real

2. highly diminished

size = 1.5 cm

Explanation:

height of object =3cm

radius of curvature = 20 cm

distance of object placed (u) =30 cm

now

we know that focal length = 2×radius of curvature

Therefore, focal length (f)= 10cm

now

by mirror formula = 1/f=1/v+1/u

= -1/10=1/v+(-1/30) ( minus is because it is placed on the right side of the mirror)

= v=-15cm

(IT MEANS THAT IMAGE IS ALSO FORMED ON THE RIGHT SIDE OF YHE MIRROR)

now

magnification =v/u=15/30=1/2

now

m=image size/object size

1/2=image size/3

image size =1.5 cm.