View Single Post
May3-09, 02:26 AM   #1
 

Mirrors (concave) + questions on lens and mirrors


1. The image of the moon is formed by a concave mirror whose radius of curvature is 4.20 m at a time when the moon's distance is 3.8 x 10^5 km. What is the diameter of the image of the moon if the diameter of the moon is 3480 km?



2. 1/f = 1/do + 1/di
M = hi/ho = - di/do




3. 1/f = 1/do + 1/di
di = dof/do - f
= 3.8 x 1065(0.0042)/3.8 x 10^5 - 0.0042
= 0.0042 km

hi/ho = - di/do
hi= ho (- di/do)
= 3480(-0.0042/3.8 x 10^5)
= -3.8 x 10^-5 km

I'm not sure if this is right. I also have some questions how do you know if it is concave or convex (lens/mirrors if the book doesn't say it), what's the difference between mirrors and lens, and how do you tell if its a converging lens or a diverging lens whats the difference between them. Thank You!! :]
PhysOrg.com science news on PhysOrg.com

>> City-life changes blackbird personalities, study shows
>> Origins of 'The Hoff' crab revealed (w/ Video)
>> Older males make better fathers: Mature male beetles work harder, care less about female infidelity