Inclined mirror problem Sir, Please see if it is right. 1)A ray of light makes an angle of 10 degrees with the horizontal and strikes a plane mirror which is inclined at an angle y to the horizontal. What is the angle y for which the reflected ray becomes vertical? I solved it in the following way: Given that angle(CBF) = 90, angle(CBD) = 10, angle(DBE) = angle(EBF) = m i.e. 2m + 10 = 90 m = 40 Now, y + 10 + 40 = 90 y = 40 Is it right?