Which postulate of Rutherford's theory is not derived from the results of `alpha`-ray scattering experiment ?
On what basis Rutherford's could assume that ?

Explanation

To answer the question, we need to identify which postulate of Rutherford's atomic theory is not derived from the alpha-ray scattering experiment and understand the basis on which Rutherford made that assumption.

### Step-by-Step Solution:

1. **Understanding Rutherford's Atomic Theory**:
- Rutherford proposed a model of the atom based on his gold foil experiment, where he observed that most alpha particles passed through the foil, but some were deflected at large angles. This led him to conclude that atoms have a small, dense nucleus.

2. **Identifying the Postulates**:
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