An electron jumps from an orbit `P` to `Q` and loses energy. The same electron when jumps from `R` to `Q` gains energy. The increasing order of distance of these orbits from the nucleus is

Options

A. `P lt Q lt R `
B. `R lt P lt Q `
C. `R lt Q lt P`
D. `P lt R lt Q`

Explanation

To solve the problem, we need to analyze the energy transitions of the electron between the orbits P, Q, and R in relation to their distances from the nucleus.

### Step-by-Step Solution:

1. **Understanding Energy Levels**:
- In an atom, electrons occupy specific energy levels or orbits around the nucleus. The energy levels are quantized, meaning electrons can only exist in certain fixed orbits.
- The energy of an electron in an orbit is inversely related to its distance from the nucleus. The closer the orbit is to the nucleus, the lower the energy level.

2. **Analyzing the Transition from P to Q**:
- The problem states that an electron jumps from orbit P to orbit Q and loses energy.
- Since the electron loses energy while moving to Q, it indicates that orbit P is at a higher energy level than orbit Q. Therefore, orbit P must be farther from the nucleus than orbit Q.

3. **Analyzing the Transition from R to Q**:
- The same electron jumps from orbit R to orbit Q and gains energy.
- This means that orbit R is at a lower energy level than orbit Q. Therefore, orbit R must be closer to the nucleus than orbit Q.

4. **Establishing the Order of Orbits**:
- From the analysis, we have established:
- P is farther from the nucleus than Q (P > Q).
- R is closer to the nucleus than Q (R < Q).
- To summarize:
- Since R is closer to the nucleus than Q, and P is farther than Q, we can conclude that R is the closest, followed by Q, and then P.

5. **Final Order of Distances**:
- The increasing order of distances from the nucleus is: R < Q < P.

### Conclusion:
The increasing order of distance of these orbits from the nucleus is **R < Q < P**.