The concept of stationary orbits was proposed by

Options

A. Neil Bohr
B. J J Thomson
C. Rutherford
D. Issac Newton

Answer

To solve the question "The concept of stationary orbits was proposed by," we will analyze the options provided and identify the correct answer based on the key concepts of atomic theory.

### Step-by-step Solution:

1. **Identify the Options**: The options given are:
- Option 1: Neil Bohr
- Option 2: J. J. Thomson
- Option 3: Rutherford
- Option 4: Isaac Newton

2. **Recall Key Concepts**: The concept of stationary orbits refers to the idea that electrons in an atom can occupy certain fixed orbits or energy levels without radiating energy. This concept is crucial in understanding atomic structure.

3. **Analyze Each Option**:
- **Neil Bohr**: He proposed the Bohr model of the atom in 1913, which introduced the idea of quantized energy levels where electrons can orbit the nucleus without emitting energy. These orbits are known as stationary states.
- **J. J. Thomson**: He is known for the discovery of the electron and the plum pudding model of the atom, but he did not propose the concept of stationary orbits.
- **Rutherford**: He conducted the gold foil experiment and proposed the nuclear model of the atom, but he did not introduce stationary orbits.
- **Isaac Newton**: He contributed to classical mechanics and gravitation, but he did not work on atomic theory or stationary orbits.

4. **Conclusion**: Based on the analysis, Neil Bohr is the scientist who proposed the concept of stationary orbits. Therefore, the correct answer is:
- **Option 1: Neil Bohr**

### Final Answer:
The concept of stationary orbits was proposed by **Neil Bohr**.

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