A current of 5.0 A exists in the circuit shown in figure. The wire PQ has a length of 50 cm and the magnetic field in which it is immersed has a magnitude of 0.20 T. Find the magnetic force acting on the wire PQ.



Given-
Length of the wire PQ inside the magnetic field, l = 50 cm
Electric current , I = 5 A
Magnetic field, B = 0.2 T



From fig since magnetic field is displayed as “cross”, we can say that the direction of magnetic field is perpendicular to the plane and it is going into the plane.




Angle between the plane of the wire and the magnetic field, θ = 900




where,


B= magnetic field


I = current


L = length of the wire


and θ = the angle between B and L








The direction of force can be found using Fleming’s left-hand rule.


whenever a current carrying conductor is placed inside a magnetic field, a force acts on the conductor, in a direction perpendicular to both the directions of the current and the magnetic field


Thus, the direction of magnetic force is upwards in the plane of the paper.


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