Quote:
Originally Posted by silent.volcano
1. Water is heated in a kettle. The inside water is heated by convection. A person sitting near the fire receives heat by :
a) Conduction
b) Convection
c) Radiation
d) Reflection
e) None of these
its answer should be radiation not conduction because conduction is the heat transferred with in the body.
when heat is radiated by the kettle the person sitting near the fire receives the heat
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While radiation is transfer of heat through empty space (without any molecules, electrons or any other material)
Convection is the transfer of heat through movement of molecules, in this case, the molecules of air (gases) transfer the heat, so correct answer is Convection. Read
http://en.wikipedia.org/wiki/Heat_transfer for more clearance of concept.
Well I personally believe that the transfer of heat is at a time by all methods but almost always one method is predominant. So we consider that as correct answer.