Question

an electric heater supplies heat to a rate of 100W If system performs work at a rate of 75 j/s at what is the internal energy increasing​

Answer 1

Given :

Heat supplied to the system = 100J/s

Workdone = 75 J/s

To find :

the internal energy of the system

Solution :

From the first law of thermodynamics that is,

» A quality of heat supplied to the system goes in partly to increase the internal energy of the system and the rest in work on the environment.

In other words,

∆Q = ∆U + ∆W

here,

• Q denotes heat supplied
• U denotes internal energy
• W denotes work done

by substituting all the given values in the formula,

$\dashrightarrow \sf Q = U + W$

$\dashrightarrow \sf 100 = U + 75$

$\dashrightarrow \sf U = 25J/s$

$\dashrightarrow \sf U = 25 \: W$

Therefore, the internal energy of the electric heater increases at a rate of 25W.