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Airforce Group X 12 Jul 2021 Shift 1 Memory Based Paper

Option 2 : weber

__CONCEPT__:

- Magnetic flux: The number of magnetic field lines passing a surface area normally is called magnetic flux. It is denoted by φ.
- Magnetic flux is mathematically equal to the dot product of the magnetic field and area vector through which it is passing.

Magnetic flux (φ) = B. A

Where B is the magnetic field and A is the area vector

- The SI unit of area is m2 and the SI unit of the magnetic field is the tesla (T).

__EXPLANATION__:

Since magnetic flux (φ) = B A

The SI unit of magnetic flux = SI unit of magnetic field × SI unit of area = tesla. meter2 = T m2

Since 1 Weber = 1 T m2

- Thus the SI unit of magnetic flux is T m2 and which is equal to weber (Wb). Hence option 2 is correct.