When `alpha` is the angle between plane of the coil and magnetic field `vecB`, flux linked with the coil is given by `phi` =____

Options

A. AB
B. `|vecAxxvecB|`
C. `AB cos alpha`
D. `vecA xx vecB`

Answer

B

Explanation

Here angle `theta` is between `vecA` and `vecB=90^@-alpha`.
`therefore phi=vecA.vecB`
`=AB cos(90^@-alpha)`
`=AB sin alpha`
`therefore phi=|vecAxxvecB|`