A 0.5m long metal rod PQ completes the circuit as shown in the figure. The area of the circuit is perpendicular to the magnetic field of flux density 0.15 T. If the resistance of the total circuit is `3Omega` calculate the force needed to move the rod in the direction as indicated with a constant speed of `2 ms^(-1)`

A straight line conductor of length 0.4 m is moved with a speed of 7ms^-1 perpendicular to magnetic field of intensity 0.9 Wb m^-2 . The induced e.m.f. across the conductor is

A conductor 2m long moves in a magnetic field of lfux density 0.5 xx 10^-4 tesla with a speedof 36 km per hour. Calculate the e.m.f. induced in it, if it is perpendicular to both its length and field.

A wire 88cm long bent into a circular loop is placed perpendicular to the magnetic field of density 2.5 Wb m^(-2) . Within 0.5 s the loop is changed into square of each side 22 cm and the density is increased to 3Wbm-2 . Calculate the value of e.m.f. induced.

Figure shows a conducting rod PQ in contact with metal rails RP and SQ, which are 0.25 m apart in a uniform magnetic field of flux density 0.4T acting perpendicular to the plane of the paper. Ends R and S are connected through a 5 Omega resistance. What is the emf when the rod moves to the right with a velocity of 5ms^(-1) ? What is the magnitude and direction of the current through the 5 Omega resistance? If the rod PQ moves to the left with the same speed, what will be the new current and its direction?

A wire 40 cm long bent into a rectangular loop 15 cmxx5 cm is placed perpendicular to the magnetic field whose flux density is 0.8 Wbm ^(-2) . Within 1.0 second, the loop is changed into a 10 cm square and flux density increases to 1.4 Wbm^(-2) . Calculate the value of induced emf.

Figure shows a metal rod PQ resting on the smooth rails AB and positioned between the poles of a permanent magnet. The rails, the rod, and the magnetic field are in three mutual perpendicular directions. A galvanometer G connects the rails through a switch K. Length of the rod =15 cm, B = 0.50 T, resistance of the closed loop containing the rod = 9.0 mOmega . Assume the field to be uniform and the rod is moved with a speed of 12 cm/s. How much power is dissipated as heat in the closed circuit? What is the source of this power? :

A straight conductor carries a current of 1.5 A and is 2 m long. is placed in a uniform magnetic field of 0.15 T Find the force on it, when it is perpendicular.

An a.c. generator consists of a coil of 100 turns and cross sectional area of 3 m^(2) , rotating at a constant angular speed of 60 rad//sec in a uniform magnetic field of 0.04 T. The resistance of the coil is 500 Omega . Calculate max. power dissipation in the coil.

A 100 turn coil of area 0.1 m^(2) rotates at half a revolution per second. It is placed in a magnetic field of 0.01 T perpendicular to the axis of rotation of the coil. Calculate the maximum voltage generated in the coil.