S.I. unit of temperature is

Options

A. cal
B. joule
C. celsius
D. kelvin

Answer

**Step-by-Step Solution:**

1. **Understanding Temperature**: Temperature is a measure of the average kinetic energy of the particles in a substance. It is an important physical quantity in various scientific fields.

2. **International System of Units (SI)**: The International System of Units (SI) is a standardized system used globally for scientific measurements. Each physical quantity has a specific unit associated with it.

3. **Identifying the Unit for Temperature**: In the SI system, the unit specifically designated for measuring temperature is the Kelvin.

4. **Symbol Representation**: The symbol for the Kelvin is 'K'. This is the notation used in scientific contexts to represent temperature in Kelvin.

5. **Conclusion**: Therefore, the S.I. unit of temperature is Kelvin, represented as K.

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