Question

An object is placed 10 cm in front of a mirror, and an image is formed that has a magnification of 2.
Which of the following statements is true?
a. The focal length of the mirror is 30 cm.
b. The image is real.
c. There is not enough information to select the correct answer.
d. This is the only true statement.

Answer 1

Answer:

None of it is right

Explanation:

u=10cm

m=2

m= -v/u (since it is a mirror)

•2= -v/10

Therefore v = -20

........

1/f = 1/v + 1/u

1/f= 1/ -20 + 1/10

= -1+2/20

= 1/20

Therefore f = 20 cm