Waber is derived unit of

Options

A. magnetic moment
B. luminous flux
C. magnetic flux
D. none of these

Answer

To determine what the weber (Wb) is a derived unit of, we can analyze the options provided: magnetic moment, luminous flux, and magnetic flux.

### Step 1: Understand the Definitions
- **Magnetic Moment**: The unit of magnetic moment is ampere-meter squared (A·m²).
- **Luminous Flux**: The unit of luminous flux is lumen (lm).
- **Magnetic Flux**: The unit of magnetic flux is defined as the product of the magnetic field (in tesla) and the area (in square meters).

### Step 2: Analyze Magnetic Flux
Magnetic flux (Φ) can be expressed mathematically as:
\[ Φ = B \cdot A \]
where:
- \( B \) is the magnetic field strength in teslas (T),
- \( A \) is the area in square meters (m²).

The unit of magnetic flux is therefore:
\[ \text{Tesla} \cdot \text{meter}^2 = \text{Wb} \]
This means that one weber (1 Wb) is equal to one tesla-meter squared.

### Step 3: Compare with Other Options
- The unit of **magnetic moment** (A·m²) is different from the weber.
- The unit of **luminous flux** (lumen) is also different from the weber.

### Conclusion
Since the weber is defined as the unit of magnetic flux, we can conclude that:

**The weber (Wb) is a derived unit of magnetic flux.**