Derived unit is

Options

A. candela
B. steradian
C. ampere
D. volt

Answer

To determine which of the given options is a derived unit, we first need to understand the difference between fundamental units and derived units.

### Step-by-Step Solution:

1. **Understanding Units**:
- Units can be classified into two categories: fundamental units and derived units.
- **Fundamental Units**: These are the basic units that cannot be derived from other units. There are seven fundamental units in the International System of Units (SI).
- **Derived Units**: These units are derived from fundamental units. They are formed by combining fundamental units through multiplication or division.

2. **Analyzing the Options**:
- **Option 1: Candela**
- Candela is the fundamental unit of luminous intensity. It is not derived from any other unit.
- **Option 2: Tiradian**
- The Tiradian is a unit of solid angle. It is also considered a fundamental unit in the context of angular measurements, not derived from other units.
- **Option 3: Ampere**
- Ampere is the fundamental unit of electric current. Like the previous two, it is not derived from other units.
- **Option 4: Volt**
- Volt is the unit of electric potential difference. It is derived from the fundamental units of mass, length, time, and electric current (1 Volt = 1 Joule/Coulomb = 1 kg·m²/(s³·A)).

3. **Conclusion**:
- Among the options provided, **Volt** is the only derived unit. Therefore, the correct answer is **Option 4: Volt**.