For a man walking on the floor, the force of friction between the floor and his feet accelerates him forword. What will be work done by the force of friction, postive, negative or zero?

Explanation

To determine the work done by the force of friction when a man is walking on the floor, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Forces Involved**:
- When a man walks, the force of friction acts between his feet and the ground. This frictional force is what allows him to push off the ground and move forward.

2. **Determine the Type of Friction**:
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