Why is the horizontal component of a velocity remains constant in horizontal and inclined projection

This is because there is no acceleration in the horizontal direction

Explanation:

This is because, the only acceleration affecting the object in horizontal and inclined projection is the acceleration due to gravity, which is directed the vertical downward direction. There is a velocity change only in the vertical direction and none in the horizontal direction because, there is no acceleration in the horizontal direction. So, its velocity remains constant.

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.

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