Question

If an object is placed at 30cm in front of a concave mirror whose focal length is 15. Then find image distance ​

Answer 1

Answer:

u= -30 cm

f= -20 cm

v=?

By using mirror formula,

$\frac{1}{v} + \frac{1}{u}=\frac{1}{f}$

$\frac{1}{v}+\frac{1}{-30}=\frac{1}{-20}$

v= -60 cm

negative sign indicates that image is in front of the mirror