Question

A concave mirror gives an image three times as
large as the object placed at a distance of 20 cm
from it. For the image to be real, the focal length
should be -
(1)-10 cm
(2) -15 cm
(3) -20 cm
(4) -30 cm​

Answer 1

Answer:

the image to BDL the focal length should be minus 10 centimetre