How does the concave mirror used in satellite dishes strengthen weak signals?

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Solution

One of the most important uses of a concave mirror is in satellite dishes. These are used to receive the weaker signals sent from the communication satellites and then amplify them. These signals strike the concave mirror in parallel rays and get reflected back. These reflected rays are concentrated at the focus of the mirror. Therefore, the main purpose of this mirror is to gather weaker signals coming from large areas and concentrate them at one point.

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