Velocity ratio is the ratio of .....

Options

A. velocity of girl to velocity of boy.
B. velocity of effort to velocity of load
C. velocity of load to velocity of effort
D. none of the above.

Explanation

To solve the question regarding the definition of velocity ratio, we can break it down step by step:

### Step-by-Step Solution:

1. **Understanding the Concept**:
- The term "velocity ratio" is commonly used in the context of simple machines. It helps us understand how much the effort (input) moves compared to the load (output).

2. **Defining the Terms**:
- **Velocity of Effort (VE)**: This is the speed at which the effort is applied to the machine.
- **Velocity of Load (VL)**: This is the speed at which the load is moved by the machine.

3. **Formulating the Velocity Ratio**:
- The velocity ratio (VR) is defined mathematically as:
\[ \text{Velocity Ratio (VR)} = \frac{\text{Velocity of Effort (VE)}}{\text{Velocity of Load (VL)}} \]

4. **Analyzing the Options**:
- Given the options:
1. Velocity of girl to velocity of boy
2. Velocity of effort to velocity of load
3. Velocity of load to velocity of effort
4. None of the above
- From our definition, we can see that the correct option is the one that matches our formula.

5. **Selecting the Correct Answer**:
- The second option, "Velocity of effort to velocity of load," matches our definition of velocity ratio.
- Therefore, the correct answer is option 2.

### Final Answer:
The velocity ratio is the ratio of velocity of effort to velocity of load.

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