The radius of curvature of a concave mirror is 24 cm and the imager is magnified by 1.5 times. The object distance is
Options
(a) 20 cm
(b) 8 cm
(c) 16 cm
(d) 24 cm
Correct Answer:
20 cm
Explanation:
R = -24 cm, f = -12 cm, m = 1.5
(1 / v) + (1 / u) = 1 / f
.·. u = 20 cm.
View Comments (1)
given that
R=24 cm
f=R/2=24/2=12 cm
and m= -v/u = -3/2........(1)
v=3/2 u .............(2)
from mirror equation,
1/v+1/u=1/f................(3)
putting the value of f and v in equation (3) we get,
2/3u+1/u=1/12
3u=60
u=20 cm