A man feels hot when he comes close to fire. Heat is transferred through?
- Conduction
- Convection
- Radiation
- Both B and C
Explanation
When a person stands near a fire, they feel hot primarily through radiation and convection.
Radiation
- This is the transfer of heat through electromagnetic waves, primarily infrared radiation, and does not require a medium (like air or water) to travel.
- Fire radiates energy in all directions, which is why you can feel the warmth even if the air around you is cold.
- When the radiant energy from the fire hits your skin, it is absorbed and converted into thermal energy, making you feel warm.
Convection
- This is the transfer of heat through the movement of a heated fluid (in this case, air).
- The air directly above the fire gets hot, becomes less dense, and rises.
- This creates air currents that carry heat upward and can warm a person standing nearby.
- However, when standing to the side of a fire, the effect of convection is usually much less than radiation, as the hottest air rises and billows away from you.
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