Q. A current of $5\ ampere$ is flowing in a wire of length $1.5\ metres$. A force of 7.5 $N$ acts on it when it is placed in a uniform magnetic field of $2\ tesla$. The angle between the magnetic field and the direction of the current is
A) $30{^\circ}$
B) $45{^\circ}$
C) $60{^\circ}$
D) $90{^\circ}$
Explanation
(a) $F = Bil\sin\theta \Rightarrow 7.5 = 2 \times 5 \times 1.5\sin\theta \Rightarrow \theta = 30{^\circ}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.