Which of the following does not change the direction of a force?

Options

A. inclined plane
B. pulley
C. wedge
D. wheel-and-axle

Explanation

To determine which of the following options does not change the direction of a force, let's analyze each option step by step:

1. **Inclined Plane**: An inclined plane allows an object to be raised by applying force along the slope. While it changes the direction of the applied force (from horizontal to vertical), it does not change the nature of the force itself.

**Hint**: Think about how an inclined plane allows you to lift an object with less effort.

2. **Pulley**: A pulley changes the direction of the force applied. When you pull down on one side of the rope, the load on the other side moves up. Thus, a pulley does change the direction of the force.

**Hint**: Consider how a pulley system allows you to lift heavy objects by pulling down.

3. **Wedge**: A wedge is used to split or separate objects. When force is applied to the wedge, it changes the direction of the force as it pushes outward to split the object. Therefore, a wedge does change the direction of the force.

**Hint**: Think about how a wedge works to push apart materials when force is applied.

4. **Wheel and Axle**: In a wheel and axle system, when you apply a force to the wheel, it rotates around the axle. The direction of the force applied does not change; it continues in the same direction as the wheel rolls. Therefore, the wheel and axle do not change the direction of the force.

**Hint**: Visualize how a wheel rolls forward without changing the direction of the force applied to it.

**Conclusion**: The correct answer is **Wheel and Axle** (Option D), as it does not change the direction of a force.

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