Q28 (2024)
An electric heater supplies heat to a system at a rate of 100 W. If the system performs work at a rate of 75 J/s, then the rate at which internal energy increases will be:
- 125 W
- 100 W
- 25 W
- 75 W
### Related Formula
$$\frac{dQ}{dt} = \frac{dU}{dt} + \frac{dW}{dt}$$
### Core Logic
$$100 \text{ W} = \frac{dU}{dt} + 75 \text{ W} \Rightarrow \frac{dU}{dt} = 25 \text{ W}$$
### Pattern Recognition
Rate form of the First Law of Thermodynamics.
### Evaluation Rubric / Model Answer
null
### Chapter Mix
Class 11 Physics: Thermodynamics
