_______ is the reason why we find it hard to move a large carton on a floor.

Options

A. Gravitational force
B. Frictional force
C. Electrostatic force
D. Muscular force

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the reason why it is difficult to move a large carton on a floor.

2. **Identifying Possible Forces**: The forces that could be involved include:
- Gravitational force
- Frictional force
- Electrostatic force
- Muscular force

3. **Analyzing Each Force**:
- **Gravitational Force**: This force keeps the carton on the floor but does not directly affect the motion of moving it.
- **Frictional Force**: This is the force that opposes the motion of one surface sliding over another. When you try to push the carton, friction acts against the direction of the push.
- **Electrostatic Force**: This force acts between charged particles and is not relevant in this context.
- **Muscular Force**: This is the force exerted by our muscles when we push the carton, but it does not explain why the motion is difficult.

4. **Conclusion**: The primary reason we find it hard to move a large carton on a floor is due to the **frictional force**. This force acts in the opposite direction to the applied force when trying to move the carton.

5. **Final Answer**: The answer to the question is **frictional force**.

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