A ball is moving on a perfectly smooth horizontal surface. If no force is applied on it, will its speed decrease, increase or remain unchanged ?

Explanation

To solve the question, we will analyze the situation using Newton's First Law of Motion, which states that an object in motion will remain in motion with the same speed and in the same direction unless acted upon by an external force.

### Step-by-Step Solution:

1. **Understanding the Scenario**:
- A ball is moving on a perfectly smooth horizontal surface. This indicates that there is no friction acting on the ball.

2. **Identifying Forces**:
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