AIIMS 2001 Physics Energy Quantization MCQ Question

In Planck's oscillator model, the energy is given by the formula $E = \frac{h u}{\exp(\frac{h u}{kT}) - 1}$. When $K = 0$, this implies that the temperature $T$ approaches absolute zero. As $T$ approaches 0, the term $\exp(\frac{h u}{kT})$ becomes very large, leading to the denominator approaching infinity. Thus, the energy $E$ approaches 0. Therefore, the correct answer is B) 0.

The other options can be analyzed as follows:

• A) $h u$: This is incorrect because at absolute zero, the energy does not equal $h u$.
• C) $K/ u$: This is not applicable since $K$ is 0, making this expression also equal to 0, but it's not the correct interpretation of the energy formula.
• D) $\infty$: This is incorrect as the energy does not approach infinity; instead, it approaches 0 as explained above.