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3 years ago

A girl stands 5m away from a large plane mirror. How far must she walk to be 2m away from her image?

Physics

1 answer:

lord [1]3 years ago

8 0

Answer:

The girl needs to walk 4m closer to the mirror if she must be 2 m away from her image.

Explanation:

Images formed by plane mirrors is due to reflection of light Plane mirrors form only virtual or imaginary images. The image formed by a plane mirror is equidistant from the mirror as the object is from the mirror. This means that the distance of the girl from the mirror which is 5m is equal to the distance of her image from the mirror.

The distance of the girl from her image when she stands 5 m from the mirror is therefore, 5m + 5m = 10 m

In order for her to be 2 m away from her image, she needs to sand at a distance half her distance from her image, that is 1/2 * 2m = 1m

Therefore, the girl needs to walk 5m - 1m = 4m closer to the mirror if she has to be 2 m away from her image.

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