What kind of mirror concave, convex or plane would be best suited for the use in a solar cooker? Why?

What kind of mirror concave, convex or plane would be best suited for the use in a solar cooker? Why? What is the role of glass sheet used in a solar cooker? Also write two disadvantages of using a solar cooker?

Concave mirror will be best suited for the use in solar cooker because it concentrates the sunlight to a point after reflection from the mirror and thus, raises the temperature of that point. Plane glass plate does not allow the infrared or heat radiation entered in the box to go outside the box thus, heating the box and creating green house effect.

The two disadvatages of using a solar cookers are:

  1. Food cannot be cooked at night and on a cloudy day by using a solar cooker.
  2. Food cannot be cooked quickly by using a solar cooker.