How does a ray of light traveling parallel to the principal axis of a concave mirror be reflected back?

Light ray will bend inwards and pass through the focus on principle axis after reflection

Explanation:

As we know that for curved mirror the equation is given as

now here we know that initially light is travelling parallel to principle axis for given concave mirror.

So here the object position must be at very large distance from the mirror

= infinite

so here by above equation we will have

now from this equation we can say

so position of image will be at focus of mirror which means the parallel light will pass through focus after reflection from mirror.

the entire statement is true and correct.  

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