
The system shows a slidable conductor of mass , which can move over frictionless and resistance less rails and , in a horizontal plane. and are separated by a very small insulator, as shown in the figure. At , a magnetic field is applied everywhere and the conductor is released from rest. Choose the correct statement (s), neglecting back emf in the conductor .


Important Questions on Moving Charges and Magnetism





An arrangement of three parallel straight wires placed perpendicular to plane of paper carrying same current along the same direction is shown in Figure. Magnitude of force per unit length on the middle wire is given by




Two long conductors, separated by a distance carry currents and in the same direction. They exert a force on each other. Now the current in one of them is increased to two times and its direction is reversed. The distance is also increased to . The new value of force between them is

Consider two straight parallel conductors and separated by a distance and carrying individual currents respectively. If the two conductors attract each other, it indicates that



A copper rod of mass slides under gravity on two smooth parallel rails distance apart and set an angle to the horizontal. At the bottom, the rails are joined by a resistance in figure. There is a uniform magnetic field perpendicular to the plane of the rails. The terminal velocity of rod is

Two long straight parallel wires, carrying (adjustable) currents and , are kept at a distance apart. If the force between the two wires is taken as 'positive' when the wires repel each other and 'negative' when the wires attract each other, the graph showing the dependence of , on the product , would be:

The magnitude and direction of a force vector acting on a unit length of thin wire carrying a current at point , if the wire has a semicircular shape of radius as shown in the figure.



Two parallel very long straight wires carrying current of each are kept at a separation of If the currents are in the same direction, the force per unit length between them is _____


A rigid square loop of side and carrying current is lying on a horizontal surface near a long current carrying wire in the same plane as shown in figure. The net force on the loop due to the wire will be:

Let and be the magnitude of the force between the two wires in setup and setup , respectively.


Two long currents carrying thin wires, both with current , are held by insulating threads of length L and are in equilibrium as shown in the figure, with threads making an angle ' ' with the vertical. If wires have a mass per unit length then the value of is:
( gravitational acceleration)

