Question
A man bought a device X which could cook pulses, vegetables and rice without using any fuel like wood, coal, kerosene or LPG, etc. This device did not work at night. It also took a lot of time for cooking.
  1. Name the device X.
  2. What is the source of energy which cooks food in this device?
  3. What is the name of the process which traps energy in this device?
  4. State one advantage (other than saving on fuel) or using such a device for cooking food.

Answer

  1. Device X is a solar cooker.
  2. Solar energy is the source of energy that cooks food in this device.
  3. Greenhouse effect is the process that traps energy in this device.
  4. The advantage of this technique is that it does not cause any pollution or harm to the environment.

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