Question

Numerical problems
1. Calculate the focal length of a concave mirror when an object is kept at a distance of
20cm and an inverted image is formed at a distance of 10 cm.
(Ans: 6.33cm)​

Answer 1

Answer:

Focal length of concave mirror, f = -20 cm

Distance of object from the mirror, u = -10 cm

use formula, 1/v + 1/u = 1/f

or, 1/v = 1/f - 1/u

or, 1/v = 1/-20 - 1/-10

or, 1/v = -1/20 + 1/10 = 1/20

or, v = +20cm

hence, image position is the 20cm right side from the pole of the concave mirror as shown in the diagram. The image is straight and bigger than the object.

Answer 2

Answer:

I don't know if you have any questions or need any further information please contact me at the