Speed of Boy & Image in Plane Mirror: A,B,C Explained

In summary, the speed of the boy and the image will be the same because the boy is running parallel to the mirror and maintaining the same distance from it. This is because the distance between the boy and the mirror remains the same, and therefore the image will also remain at the same distance from the mirror. This is supported by the principle of reflection, which states that the angle of incidence is equal to the angle of reflection, and since the boy is running parallel, the incident and reflected angles will be the same. Therefore, the image and the boy will have the same speed.
  • #1
Faris1985
3
0
Q. If a boy is at a distance of 40m from a plane mirror and runs parallel to the plane of the mirror while maintaining the same distance from the mirror what will be the speed of the image and the boy.
A. Same
B. The boy has greater speed than his image
C. The image has greater speed than the boy
Please explain why for each A,B or C.
 
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  • #2
Faris1985 said:
Please explain why
This is directed at you, not us.
 
  • #3
Faris1985 said:
Q. If a boy is at a distance of 40m from a plane mirror and runs parallel to the plane of the mirror while maintaining the same distance from the mirror what will be the speed of the image and the boy.
A. Same
B. The boy has greater speed than his image
C. The image has greater speed than the boy
Please explain why for each A,B or C.

Think of it. If the boy runs parallel maintaining a same distance, how would it be different from the same boy running towards the mirror.
Also, think of what the distance of image and object is from the mirror and with respect to each other.
If you do a little pondering, you would answer it.
 

1. How is the speed of a boy and the image in a plane mirror related?

The speed of the boy and the image in a plane mirror are not directly related. The boy's speed is determined by his physical movement, while the image in the mirror is simply a reflection of that movement. The image appears to move at the same speed as the boy due to the principles of reflection, but it is not actually moving at all.

2. Why does the image in a plane mirror appear to move at the same speed as the boy?

This phenomenon is known as the law of reflection. According to this law, the angle of incidence (the angle at which the light hits the mirror) is equal to the angle of reflection (the angle at which the light bounces off the mirror). Since the boy and his image are at the same distance from the mirror, the angles of incidence and reflection are equal, making the image appear to move at the same speed as the boy.

3. Can the speed of the boy and the image in a plane mirror ever be different?

No, the speed of the boy and the image in a plane mirror will always be the same due to the law of reflection. However, if the mirror is moving or if there are other external factors affecting the reflection, the speed of the image may appear to be different from the boy's actual speed.

4. How does the distance between the boy and the plane mirror affect the speed of the image?

The distance between the boy and the plane mirror does not affect the speed of the image. As long as the boy and the mirror are at the same distance, the image will appear to move at the same speed as the boy. However, if the distance between the boy and the mirror changes, the size of the image will also change, making it seem like the image is moving faster or slower.

5. Is the speed of the image in a plane mirror affected by the size of the mirror?

No, the size of the plane mirror does not affect the speed of the image. As long as the mirror is flat and the boy and the mirror are at the same distance, the image will always appear to move at the same speed as the boy. However, a larger mirror may create a larger image, making it seem like the image is moving faster even though its speed remains the same.

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