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Question
What is the magnitude of magnetic force per unit length on a wire carrying a current of 8 A and making an angle of 30° with the direction of a uniform magnetic field of 0.15 T?
Solution
Current in the wire, I = 8 A
Magnitude of the uniform magnetic field, B = 0.15 T
Angle between the wire and magnetic field, θ = 30°
Magnetic force per unit length on the wire is given as:
f = BI sinθ
= 0.15 × 8 × 1 × sin 30°
= 0.6 N m–1
Hence, the magnetic force per unit length on the wire is 0.6 N m–1.
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