Calculating Image Height of Flower in Convex Mirror | Homework Question

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Brittany King
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1. Homework Statement

A convex spherical mirror with a focal length of magnitude 25 cm has a 4.0-cm tall flower placed 100 cm in front of it. What is the height of the image of the flower?

a.20 cm
b. 1.6 cm
c .0.80 cm
d. 4.0 cm
e. 8.0 cm

Homework Equations



1/f=1/do+1/di

M=-di/do=hi/ho

The Attempt at a Solution


[/B]
Using mirror equation I calculated di=33.3cm
Using Magnification equation I calculated hi=1.33cm

I thought this would be a simple problem, I don't see my mistake. Do any of you? Thanks in advance.
 
on Phys.org
you have used the correct equations, but you forget about the focal length of convex mirror is virtual, hence you should substitutes f = -25 cm, and you should get di = -20 cm , hence, hi = 0.80 cm
 
yihloong said:
you have used the correct equations, but you forget about the focal length of convex mirror is virtual, hence you should substitutes f = -25 cm, and you should get di = -20 cm , hence, hi = 0.80 cm
Hello yihloong, :welcome:

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