It is easier to draw up a wooden block along an inclined plane than haul it up vertically because

Options

A. a) The friction is reduced
B. b) The mass becomes smaller
C. c) g becomes smaller
D. d) Only a part of the weight has to be overcome

Explanation

To solve the question, "It is easier to draw up a wooden block along an inclined plane than haul it up vertically because...", we can analyze the forces acting on the block in both scenarios.

### Step-by-Step Solution:

1. **Understanding the Forces**:
- When a block of mass \( m \) is held vertically, the force required to lift it is equal to its weight, which is given by \( W = mg \), where \( g \) is the acceleration due to gravity.

2. **Analyzing the Inclined Plane**:
- When the same block is drawn up an inclined plane at an angle \( \theta \), the weight of the block can be resolved into two components:
- One component acts perpendicular to the inclined plane.
- The other component acts parallel to the inclined plane, which is responsible for pulling the block down the slope.

3. **Calculating the Parallel Component**:
- The component of the weight acting parallel to the inclined plane is given by:
\[ W_{\parallel} = mg \sin(\theta) \]
- This means that when pulling the block up the inclined plane, you only need to overcome this parallel component of the weight.

4. **Comparison of Forces**:
- The force required to pull the block up the inclined plane is less than the force required to lift it vertically. This is because:
\[ W_{\parallel} = mg \sin(\theta) < mg \]
- Therefore, the force needed to draw the block up the inclined plane is less than the weight of the block.

5. **Conclusion**:
- Since only a part of the weight (the parallel component) needs to be overcome when pulling the block up the inclined plane, it is easier to draw it up this way compared to lifting it straight up vertically.

### Final Answer:
The correct option is **D: Only a part of the weight has to be overcome**.

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