A particle of mass `m` is moving along the line `y=b,z=0` with constant speed `v`. State whether the angular momentum of particle about origin is increasing. Decreasing or constant.

Explanation

To determine whether the angular momentum of a particle moving along the line \( y = b \) and \( z = 0 \) with constant speed \( v \) is increasing, decreasing, or constant, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Motion of the Particle**:
The particle is moving in the XY plane since \( z = 0 \). The line \( y = b \) indicates that the particle's y-coordinate remains constant at \( b \) while it moves along the x-axis.

2. **Understand Angular Momentum**:
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