Class 11 Physics - Chapter Thermodynamics NCERT Solutions | An electric heater supplies heat to a sy
An electric heater supplies heat to a system at a rate of 100W. If system performs work at a rate of 75 Joules per second. At what rate is the internal energy increasing?
Heat is supplied to the system at a rate of 100 W.
∴Heat supplied, Q = 100 J/s
The system performs at a rate of 75 J/s.
∴Work done, W = 75 J/s
From the first law of thermodynamics,we have:
Q = U + W
Where, U = Internal energy
∴U = Q - W
= 100 - 75
= 25 J/s
= 25 W
Therefore, the internal energy of the given electric heater increases at a rate of 25 W.
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