For scattering by an .inverse square. field (such as that produced by a charged nucleus in Rutherford.s model), the relation between impact parameter b and the scattering angle `theta` is given by,
`b=(Ze^(2)cot theta//2)/(4pi epsilon_(0)((1)/(2)mv^(2)))`
Why is it that the mass of the nucleus does not enter the formula above but its charge does ?

Explanation

To understand why the mass of the nucleus does not enter the formula for the impact parameter \( b \) in scattering by an inverse square field, we can analyze the situation step by step.

### Step-by-Step Solution:

1. **Understanding the Formula**:
The formula given is:
\[
b = \frac{Ze^2 \cot(\theta/2)}{4\pi \epsilon_0 \left(\frac{1}{2}mv^2\right)}
...