Question

Consider a 10-cm long portion of a straight wire carrying a current of 10 A placed in a magnetic field of 0.1 T making an angle of 53° with the wire. What magnetic force does the wire experience?

Answer 1

Given:
A straight wire of length, l = 10 cm
Electric current flowing through the wire, I = 10 A
Magnetic field, B = 0.1 T
Angle between the wire and magnetic field, θ = 53˚
Magnetic force,
$\overrightarrow{F}=I\overrightarrow{l}\times \overrightarrow{B}$
∴$\left|\overrightarrow{F}\right|$ = IlBsinθ
∴$\left|\overrightarrow{\mathit{F}}\right|$ = IlBsin53˚
$\Rightarrow$F = 10 × 10 × 10⁻² × 0.1 × 0.798
$\Rightarrow$ $\overrightarrow{F}$= 0.0798$\approx$0.08 N
The direction of force can be found using Fleming's left-hand rule.
Therefore, the direction of magnetic force is perpendicular to the wire as well as the magnetic field.