- #1
roam
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Homework Statement
A dentist uses a spherical mirror to examine a tooth. The tooth is 1.13 cm in front of the mirror, and the image is formed 10.8 cm behind the mirror. Determine the mirror's radius of curvature.
Homework Equations
1/p+1/q=1/f
f=R/2
The Attempt at a Solution
Since the object is in front of the mirror, p > 0. With the image behind the mirror q < 0. So the radius of curvature is
[tex]\frac{2}{R}=\frac{1}{p} + \frac{1}{q} = \frac{1}{1.13} - \frac{1}{10.8} = \frac{10.8-1.13}{10.8}[/tex]
So [tex]R = 2 \frac{10.8}{9.67} = 2.233[/tex]
Why is my answer is wrong? I think I used the correct equations. I tried the same question with different numbers and the computer still marks my answer wrong. Any explanation would be appreciated.