Why do we feel warmer in winter under two blankets than under one?
- ATwo blankets compress the air between the body and the blanket
- BTwo blankets are thicker, so they generate more heat
- CTwo blankets enclose a layer of air which does not let the cold in
- DNone of the above
Show answer and explanation
Correct answer: (c) Two blankets enclose a layer of air which does not let the cold in
Explanation
Two blankets trap a layer of air between them. Still air is a very poor conductor of heat and, when trapped, it cannot carry heat away by convection either.
This layer stops the body's heat from escaping. The blankets do not produce heat themselves. They only reduce the loss of the body's own heat. For the same reason, several thin layers of clothes keep us warmer than one thick layer.