Question

calculate the focal length of a concave mirror if it gives three times enlarged image in front of it​

Answer 1

Answer:

Hey!

Given,

Magnification, m=3

Object distance, u=10cm

We know,

Magnification, m=−uv3= −10−v

⇒ v=30cm

From mirror formula,

f1

= v1 + u1f1

= 301 − 101 = 30×1010−30

= 300−20

f=−15cm

Focal length, f=−15cm

Hope it will be helpful ✌️