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: f = -15

Explanation:

m=3

u= -10

hi÷ho=-v÷u

3=-v÷-10

3= v÷ 10

30=v

by mirror formula

1÷f=(1÷v)+(1÷u)

1 ÷ f = 1 ÷ 30 + 1 ÷ (-10)

1 ÷ f = 1 ÷ 30 - 1 ÷ 10

=1 - 3 ÷ 30

1 ÷ f = -2 ÷ 30

1 ÷ f = -1 ÷ 15

f = - 15

The image will be erect, virtual and highly magnified

Answer 2

Answer:

focal length is -15 CM (centimeters)