Which of the following is correct for the reflected ray if a light ray strikes a plane mirror at an angle of 50° from the normal?
a. 40° from the surface of the mirror
b. 40° from the normal
c. 50° from the surface of the mirror
d. 90° from the normal
I have been stuck on this question for a while and I think it is because I am not sure I truly understand the question so I am not entirely convinced that I know the correct answer. I think the answer is either 40 degrees from the normal or 90 degrees from the normal but I do not know for sure. If you could help me answer this question and explain it to me it would be greatly appreciated.
The angle of reflection is the same as the angle of incidence.
Since incidence is 50° from the normal, so is the reflection.
Since the normal is 90° from the surface,
50° from normal = 40° from surface
So, the answer is (a)
To determine the correct answer for the reflected ray, we need to understand the concept of reflection. When a light ray strikes a plane mirror, it follows the law of reflection, which states that the angle of incidence is equal to the angle of reflection.
In this case, the light ray strikes the plane mirror at an angle of 50° from the normal. The normal is an imaginary line perpendicular to the surface of the mirror at the point of incidence, which is the point where the light ray intersects the mirror.
Now let's analyze the answer choices:
a. 40° from the surface of the mirror: This option does not align with the law of reflection. The angle of reflection should be equal to the angle of incidence, not 40°.
b. 40° from the normal: This option seems to align with the law of reflection. The angle of reflection would indeed be equal to the angle of incidence, which is 50° from the normal.
c. 50° from the surface of the mirror: This option is not accurate as the angle of reflection should match the angle of incidence, not be equal to the angle from the surface of the mirror.
d. 90° from the normal: This option does not align with the law of reflection. The angle of reflection should be equal to the angle of incidence, not 90°.
Therefore, the correct answer is b. 40° from the normal. The angle of reflection will be equal to the angle of incidence, which is 50° from the normal.
To determine the correct answer, you need to understand the concept of reflection and how it relates to angles.
When a light ray strikes a plane mirror, it follows the law of reflection. According to this law, the angle of incidence (the angle between the incident ray and the normal) is equal to the angle of reflection (the angle between the reflected ray and the normal).
In this case, the angle of incidence is given as 50° from the normal. So, the reflected ray will have the same angle with respect to the normal as the incident ray does.
Let's evaluate the options one by one:
a. 40° from the surface of the mirror
This option states that the angle of reflection is 40° from the surface of the mirror. However, the question asks for the angle from the normal, not the surface of the mirror. So, we can rule out this option.
b. 40° from the normal
This option suggests that the angle of reflection is 40° from the normal. It is a possibility, but let's evaluate the remaining options before making a final decision.
c. 50° from the surface of the mirror
Similar to option a, this option mentions the angle from the surface of the mirror, not the normal. Therefore, we can eliminate this option as well.
d. 90° from the normal
This option suggests that the angle of reflection is 90° from the normal. Although this can occur, it would mean that the reflected ray is perfectly perpendicular to the mirror's surface. Given that the incident ray strikes the mirror at a 50° angle from the normal, it is unlikely that the reflected ray would be perpendicular to the mirror.
Based on the evaluation, option b (40° from the normal) is the correct answer.