Which of the following methods can be used to measure the speed of light in laboratory?

Options

A. Roemer method
B. Fizeau method
C. Foucault Method
D. Michelson method

Answer

To solve the question regarding the methods that can be used to measure the speed of light in a laboratory, we will analyze the options and focus on the Foucault method.

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks about methods to measure the speed of light in a laboratory setting.

2. **Identifying Common Methods**:
- There are several methods historically used to measure the speed of light, including:
- Foucault method
- Michelson method
- Rotating mirror method
- Time-of-flight method

3. **Foucault Method**:
- The Foucault method involves a rotating mirror and a light source. Light is emitted from a source, reflects off a rotating mirror, travels to a distant stationary mirror, and then returns to the rotating mirror.
- The rotation of the mirror causes the returning light to be deflected at an angle, which can be measured. By knowing the distance to the stationary mirror and the angle of deflection, the speed of light can be calculated.

4. **Conclusion**:
- Among the methods listed, the Foucault method is specifically mentioned as a viable method for measuring the speed of light in the laboratory.

5. **Final Answer**:
- The Foucault method can be used to measure the speed of light in the laboratory.