Two mirrors are placed perpendicular to each other. A ray strikes the ...
Let ray strikes the vertical mirror by angle of incidence θ. Then by joining the perpendiculars of two mirrors it is clear from the diagram that angle of incidence at the horizontal mirror is (90−θ).
∴ reflected ray from the horizontal mirror makes angle θ with the horizontal mirror also incident ray at vertical mirror makes angle θ with horizontal axis.
∴ reflected ray is parallel to the original ray.
This is true for two perpendicular mirrors fixed at any positions.
Two mirrors are placed perpendicular to each other. A ray strikes the ...
Explanation:
When a ray of light strikes a mirror, it undergoes reflection, which means it changes its direction. The angle of incidence is equal to the angle of reflection.
When two mirrors are placed perpendicular to each other, the incident ray strikes the first mirror at an angle, and after reflection, it falls on the second mirror. The second mirror reflects the ray again, and the question is asking about the direction of the ray after the second reflection.
To solve this problem, we need to apply the laws of reflection. The angle of incidence is equal to the angle of reflection, and the incident ray and the reflected ray lie in the same plane as the normal to the surface of the mirror.
So, here are the steps to find the direction of the ray after the second reflection:
Step 1: Draw a diagram
Draw a diagram to represent the situation, with two mirrors placed perpendicular to each other, and the incident ray striking the first mirror at an angle.
Step 2: Apply the laws of reflection
Using the laws of reflection, we can find the direction of the reflected ray from the first mirror. The angle of incidence is equal to the angle of reflection, so the reflected ray will make an angle equal to the incident angle with the normal to the surface of the first mirror.
Step 3: Find the direction of the ray after the first reflection
The reflected ray from the first mirror will fall on the second mirror, and again, we can use the laws of reflection to find its direction after the second reflection. The incident angle will be equal to the reflected angle from the first mirror, and the normal will be perpendicular to the second mirror.
Step 4: Determine the direction of the ray after the second reflection
The direction of the reflected ray from the second mirror will be parallel to the incident ray, because the incident angle and the reflected angle are equal, and the normal to the second mirror is perpendicular to the first mirror.
Therefore, the correct answer is option B, the ray will emerge parallel to the original ray after the second reflection.