In Rutherford scattering experiment, what will be the correct angle for `alpha` scattering for an impact parameter `b = 0` ?

Explanation

To solve the problem regarding the Rutherford scattering experiment, we need to determine the scattering angle (θ) for alpha particles when the impact parameter (b) is equal to 0.

### Step-by-Step Solution:

1. **Understanding the Impact Parameter**:
The impact parameter (b) is defined as the perpendicular distance from the center of the target nucleus to the trajectory of the incoming alpha particle. When b = 0, it means that the alpha particle is aimed directly at the center of the nucleus.

2. **Using the Relation Between Impact Parameter and Scattering Angle**:
...