Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
A ray of light is incident on a plane mirror at an angle of $30^{\circ}$. At what angle with the horizontal must a plane mirror be placed so that the reflected ray becomes vertically upwards?
PhysicsRay OpticsVITEEEVITEEE 2015
Options:
  • A $40^{\circ}$
  • B $20^{\circ}$
  • C $30^{\circ}$
  • D $60^{\circ}$
Solution:
1694 Upvotes Verified Answer
The correct answer is: $30^{\circ}$
When a light ray falls on a mirror at an angle $30^{\circ}$, then the reflected ray will make the same angle with the plane as shown in Fig. (i)


In order to make the reflected ray vertical, the mirror should be rotated at an angle of $60^{\circ}$.
So, the mirror should be tilted by $\frac{60^{\circ}}{2}=30^{\circ}$ Fig. (ii)

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.