1. The problem statement, all variables and given/known data 1. A student wishes to place an object in front of a concave mirror in order to produce an image one-half the object's size. If the focal length of the mirror is 5.0cm, how far from the mirror should the object be placed? ANS : 15 cm. 2.An object is placed 2.0cm beyond the centre of curvatur of a concave mirror. If the magnification of this object is 0.30 what is the radius of curvature of this mirror. ANS: 1.7cm 2. Relevant equations 1/f = 1/do + 1/di m = hi/ho = -di/do 3. The attempt at a solution 1. I believe these are questions where you have to combine two formulas, i dont know how to go about it, im not asking for full work, if oyu decide to show full steps, im trying to figure it out and i cant seem to do it, can someone start me off on the right track? Or if im overthinking it put me on the right track. 1) 1/2ho/ho= f-do/do 1/2do=-f-do 2do=-2f which would be -5, which isnt right.