physics
posted by Tom .
A 4.5 cm tall object is placed 20 cm in front of a spherical mirror. It is desired to produce a virtual image that is upright and 3.5 cm tall.
(a) What type of mirror should be used?
concave mirror
convex mirror
(b) Where is the image located? (Your answer should be positive if the image is in front of the mirror and negative if the image is behind it.)
cm
(c) What is the focal length of the mirror?
cm
(d) What is the radius of curvature of the mirror?

Part (a) should be convex.
Part (b)You have to put the height of your image over the height of your object, like a ratio. Once you do that, multiply that answer by the "20cm." Your answer should be a negative.
Part (c) Use the equation: 1/do+1/di=1/f
Part (d) Multiply the answer you got for part (c) by two 
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