KCET2016PhysicsThermal Properties of Matter
Four rods with different radii ( r ) and length ( l ) are used to connect two heat reservoirs at different temperature. Which one will conduct most heat?
Options
- A( r=1 ~cm , l=1 ~m )
- B( r=1 ~cm , l= 1 2 m )
- C( r=2 ~cm , l=2 ~m )
- D( r=2 ~cm , l= 1 2 m )
Correct answer
D. ( r=2 ~cm , l= 1 2 m )
Step-by-step solution
The amount of heat conducted depends on radii r andlength I as ( Q r² l ) Thus, rod will conduct maximum for maximum r value and minimum I value, Therefore, ( r=2 ~cm ) and ( l= 1 2 m )