Question

(a) With the help of a labelled diagram, explain the construction and working of a solar cooker.
(b) Why is the solar cooker box painted black from inside?
(c) Why is the solar cooker box covered with a glass sheet?

Answer 1

(a) A solar cooker is illustrated below.

Construction:
A mirror, black box and glass lid are required to construct a solar cooker..
The mirror is mounted on the box to concentrate light rays onto the cooker box. The box is painted back from the inside to absorb the maximum light. It is covered with a glass lid to produce a greenhouse effect inside it. See the diagram given above.

Explanation:
A solar cooker is a device in which heat energy from sunlight is trapped inside the cooker using the phenomenon of the greenhouse effect.
A solar heating device such as a solar cooker uses a reflector to reflect sunlight to a small area where the cooking container is placed. The light from the sun is focussed on the container, which gets heated, cooking the food.

(b) A solar cooker box is painted back from the inside so that light is not reflected and the maximum absorption takes place.

(c) A solar cooker is covered with a glass sheet to produce a greenhouse effect inside the cooker box. The greenhouse effect is a phenomenon by which heat is trapped.