Question

A 12-inch object is placed 30 inches in front of a plane mirror. A ray of light from the object strikes the mirror at a 45-degree angle. How tall is the image produced by the mirror

Answer 1

As we know,
Image distance with respect to mirror = object distance with respect to mirror
e.g., $\bold{|X_{im}| = |X_{om}|}$

Here , when a ray of light from the object strikes the mirror at a 45° degree , it can't defect in height of image . Because image distance with respect to mirror and object distance with respect to mirror are always constant.
Use, similarity cincepts to find height of image,
e.g.,height of object/object distance with respect to mirror = height of image/image distance with respect to mirror
Here , object distance with respect to mirror, Xom = 30 inches
Height of object = 12 inches

So, 12 inches/30 = height of image/30
Height of image = 12 inches