# Few Mirror Questions

1. Apr 10, 2005

### Kdawg

I have a few mirror questions. I missed class and didnt get the formulas to do these. If some one could help me out it would be appriciated. The formulas I have in my notes are 1/f = 1/do + 1/di and hi = (ho * di) / do. I dont think I have enough info to use these formulas and im guessinf there is a formula or two I am missing.

1.)A dentist uses a small mirror of radius 55 mm to locate a cavity in a patient's tooth. If the mirror is concave and is held 10 mm from the tooth, what is the magnification of the resulting image?

2.)A production line inspector wants a mirror that produces an upright image within magnification of 7.0 when it is located 18.0 mm from a machine part.
What is its radius of curvature?

3.)Shiny lawn spheres placed on pedestals are convex mirrors. One such sphere has a diameter of 48 cm. A 12 cm robin sits in a tree 2.3 m from the sphere. Where is the image of the robin? How long is the robin's image?

4.)The image of the moon is formed by a concave mirror whose radius of curvature is 4.41 m at a time when the moon's distance is 3.80 105 km. What is the diameter of the image if the diameter of the moon is 3480 km?

5.)A shaving mirror has a radius of curvature of 33.0 cm. When a face is 11.0 cm away from the mirror, what is the magnification of the mirror?

2. Apr 11, 2005

### SpaceTiger

Staff Emeritus
You really should show your work when posting here. For standard mirror equations, you'll need to do a web search.