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CONCEPT:
- Solar cooker: It is a device that uses the energy of sunlight to heat or cook food
- Concave Mirror: Those mirrors have a reflecting surface as a curved inward that absorbs all the light coming towards them.
- It is also known as a Converging mirror.
- Concave mirrors are used for solar energy storage in solar cookers.
EXPLANATION:

- A solar cooker contains a box made of insulating material, with its inner surfaces blackened. The top is closed by a glass sheet.
- Concave Mirror is used in solar cookers to absorbs all the light coming from the infinite which are brought together near at the focus, cause the production of lots of heat in it.
- The temperature at that point increases which heats and cooks the food placed at that point.
- The efficiency of this solar cooker can be increased by placing a plane mirror at some inclination with the glass top to enhance more trapping of sunlight.

