Calculating Image Height of Flower in Convex Mirror | Homework Question

AI Thread Summary
The problem involves calculating the height of an image of a flower using a convex mirror with a focal length of -25 cm. The initial calculations incorrectly used a positive focal length, leading to an incorrect image distance (di) of 33.3 cm and image height (hi) of 1.33 cm. The correct approach requires using the negative focal length, resulting in a di of -20 cm and an image height of 0.80 cm. The discussion emphasizes the importance of understanding the virtual nature of the focal length in convex mirrors. Overall, the correct image height of the flower is 0.80 cm.
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.
 
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Please, show the steps in your calculation...
 
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:

Please note that in PF we don't provide the answers: we help the posters learn and understand by pointing at mistakes and by asking relevant questions. Directly giving an answer often robs the poster from a valuable learning experience
 
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