Answer to Question #2736 in Optics for rene
object distance from mirror = u (Object is your face)
Image distance from mirror = v
(a)& The image appears behind the mirror, and your face is in front, so the
distance from your face to the image is u + v
So u + v = 40
also magnification = v/u so v/u = 1.5
Therefore v = 1.5u and u + v = 40
Combining these two:-
u + 1.5u = 40
2.5u = 40
Your distance from mirror& u = 40/2.5 = 16cm.
also v = 1.5u
so v = 1.5 * 16 = 24cm.
The equation to find the focal length "f" is
1/u + 1/v = 1/f
so 1/f = 1/16 + 1/24
1/f = 3/48 + 2/48 = 5/48
so 1/f = 5/48
& Hence f = 48/5 = 9.6cm.
The radius of curvature of a concave mirror is twice the focal length f, so:
R = 2 * 9.6 = 19.2cm.
Need a fast expert's response?Submit order
and get a quick answer at the best price
for any assignment or question with DETAILED EXPLANATIONS!