Mechanical advantage is ratio of .............

Options

A. load to effort
B. effort to load
C. useful effort to load
D. useful load to useful effort.

Explanation

**Step-by-Step Solution:**

1. **Understanding Mechanical Advantage**:
- Mechanical advantage (MA) is a concept used to describe the efficiency of a simple machine. It indicates how much a machine amplifies an input force (effort) to lift a load.

2. **Defining Mechanical Advantage**:
- The mechanical advantage is mathematically defined as the ratio of the load (the output force) to the effort (the input force) applied to the machine.
- This can be expressed as:
\[ \text{Mechanical Advantage (MA)} = \frac{\text{Load}}{\text{Effort}} \]

3. **Identifying the Correct Option**:
- Given the options:
1. Load to Effort
2. Effort to Load
3. Useful Effort to Load
4. Useful Load to Useful Effort
- Based on the definition, the correct option that matches the formula is:
- **Option 1: Load to Effort**

4. **Conclusion**:
- Therefore, the answer to the question "Mechanical advantage is the ratio of ............." is **Load to Effort**.

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