If only an external force can change the state of motion of CM of a body then how does the internal force of the brakes bring bicycle to rest?

Explanation

To understand how the internal force of the brakes can bring a bicycle to rest, we need to analyze the forces acting on the bicycle and the concept of the center of mass (CM).

### Step-by-Step Solution:

1. **Understanding the Center of Mass (CM)**:
- The center of mass of a body is the point where the mass of the body is concentrated. The motion of the center of mass is influenced by external forces.

2. **Identifying Forces on the Bicycle**:
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