A parabolic section of wire OA is located in the x-y plane and carries current `I=12 A`. A uniform magnetic field `B=4.0 T` making an angle `60^(@)` with x axis exists in x-y plane. Calculate the magnetic force on the wire OA. Coordinates of A are (0.25 m, 1 m)

Options

A. `6(sqrt3-4)hatkN`
B. `6(4-sqrt3)hatkN`
C. `3(sqrt3-4)hatkN`
D. 3(4-sqrt3)hatkN`

Answer

A

Explanation

Magnetic field is uniform, apply `vecF=IveclxxvecB`
where `vecL=0.25hati+hatj` and `vecB=4(cos60hati+sin60hatj)`