To solve the question "Which physical quantity unit is same in all systems?", we can follow these steps:
### Step-by-Step Solution:
1. **Identify the Different Systems of Measurement**:
- The three main systems of measurement we will consider are:
- CGS (Centimeter-Gram-Second)
- MKS (Meter-Kilogram-Second, also known as SI units)
- FPS (Foot-Pound-Second)
2. **Examine the Units of Each Physical Quantity**:
- We will analyze the units of length, mass, time, and temperature in each system.
3. **Check the Unit for Length**:
- In CGS, the unit of length is centimeters (cm).
- In MKS, the unit of length is meters (m).
- In FPS, the unit of length is feet (ft).
- Since the units are different, length is not the same in all systems.
4. **Check the Unit for Mass**:
- In CGS, the unit of mass is grams (g).
- In MKS, the unit of mass is kilograms (kg).
- In FPS, the unit of mass is pounds (lb).
- Since the units are different, mass is not the same in all systems.
5. **Check the Unit for Time**:
- In CGS, the unit of time is seconds (s).
- In MKS, the unit of time is seconds (s).
- In FPS, the unit of time is seconds (s).
- Since the unit of time is the same across all systems, time is the correct answer.
6. **Check the Unit for Temperature**:
- In CGS, temperature can be measured in degrees Celsius (°C).
- In MKS, temperature can be measured in Kelvin (K).
- In FPS, temperature can be measured in degrees Fahrenheit (°F).
- Since the units are different, temperature is not the same in all systems.
7. **Conclusion**:
- After analyzing all the physical quantities, we conclude that the only unit that is the same in all systems is time, measured in seconds.
### Final Answer:
The physical quantity unit that is the same in all systems is **Time** (measured in seconds).
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