Question

A concave mirror produces three times enlarged image of an object placed at 10 cm in front of it. Calculate the focal length of the mirror

Answer 1

Answer:

Explanation:

m = -v/u

=> 3 = -v/-10

=> v = 30 cm..

Now, 1/f = 1/v + 1/u

=> 1/f = 1/30 - 1/10

=> 1/f = 1-3/30

=> 1/f = -2/30

=> f = -15 cm...