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Question
A semicircular wire of radius 5.0 cm carries a current of 5.0 A. A magnetic field B of magnitude 0.50 T exists along the perpendicular to the plane of the wire. Find the magnitude of the magnetic force acting on the wire.
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Solution
Given,
Radius of semicircular wire, r = 5.0 cm
Thus, the length of the wire = 2r
Electric current flowing through wire = 5.0 A
Magnetic field, B = 0.50 T
Direction of magnetic field is perpendicular to the plane of the wire which implies that angle between length of the wire and magnetic field, θ = 90˚
As we know the magnetic force is given by
`vecF = I vecl xx vecB`
`vecF = I2rBsin90^circ`
= 5 × 2 × 0.5 × =0.25 N
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