The mechanical advantage of an ideal single movable pulley is:

Options

A. 1
B. 2
C. less than 2
D. less than 1

Answer

To find the mechanical advantage (MA) of an ideal single movable pulley, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Mechanical Advantage**:
Mechanical Advantage (MA) is defined as the ratio of the load (weight being lifted) to the effort (force applied). It can be expressed mathematically as:
\[ \text{MA} = \frac{\text{Load (L)}}{\text{Effort (E)}} \]

2. **Analyze the Pulley System**:
In an ideal single movable pulley, the load is supported by the tension in the rope. When you pull down on the rope, the tension in the rope is transmitted to lift the load.

3. **Identify Forces in the System**:
For a single movable pulley, the load (L) is balanced by the tension (T) in the rope. Since the rope passes over the pulley, there are two segments of the rope supporting the load. Therefore, we can express the balance of forces as:
\[ L = T + T = 2T \]

4. **Relate Effort to Tension**:
The effort (E) applied to lift the load is equal to the tension in one segment of the rope:
\[ E = T \]

5. **Substitute Values into the MA Formula**:
Now, substituting the expressions for load and effort into the mechanical advantage formula:
\[ \text{MA} = \frac{L}{E} = \frac{2T}{T} \]

6. **Simplify the Expression**:
Simplifying the equation gives:
\[ \text{MA} = 2 \]

7. **Conclusion**:
Therefore, the mechanical advantage of an ideal single movable pulley is **2**.

### Final Answer:
The mechanical advantage of an ideal single movable pulley is **2**.

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