The S.I. unit of electric charge is___________

Options

A. ampere
B. volt
C. joule
D. coulomb

Explanation

**Step-by-Step Solution:**

1. **Understanding Electric Charge**: Electric charge is a fundamental property of matter that causes it to experience a force when placed in an electromagnetic field.

2. **Identifying the S.I. Unit**: The S.I. (International System of Units) provides a standard unit for measuring various physical quantities. For electric charge, the standard unit is defined.

3. **Defining the Unit**: The S.I. unit of electric charge is called the Coulomb. It is denoted by the symbol 'C'.

4. **Relation to Other Units**: To understand the Coulomb better, it's helpful to know that 1 Coulomb is equivalent to the amount of charge transferred by a current of 1 Ampere in 1 second. This relationship helps in understanding how electric charge is measured in practical scenarios.

5. **Conclusion**: Therefore, the answer to the question is that the S.I. unit of electric charge is Coulomb.

**Final Answer**: The S.I. unit of electric charge is **Coulomb**.

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