A concave mirror of focal length =10 cm is placed 15 cm from a square. The square lie on the principal axis i.e it's one side coincides with the principal axis. What is the perimeter of the image? How to find it?
My Approach: I found image distance as -30 cm using mirror formula taking object distance as -15 cm and focal length as -10 cm. Then using this:
Magnification = Image Length/Object length = - Image distance/Object Distance
I found the side of image square as 0.02 cm. However the book states that the perimeter is 10 mm. Also the image is not a square. How?