Two insulated circular loops A and B of radius 'a' carrying a current of 'I' in the anti clockwise direction as shown in the figure. The magnitude of the magnetic induction at the centre will be : [figure]
(2) 0 I 2a
Each loop at its centre: B= 0 I2a, along its own axis
the loops are in perpendicular planes, BA BB
[figure]
Bnet= BA2+BB2= 2 0 I2a= 0 I 2a
Answer: (2)
The horizontal component of earth's magnetic field at a place is 3.5 10-5 T. A very long straight conductor carrying current of 2 A in the direction from South east to North West is placed. The force per unit length experienced by the conductor is 10-6 N/m.
A current of 5 A flows in a square loop of side 1 m placed in air. The magnetic field at the centre of the loop is X 2 10-7 T. The value of X is .
The deflection in moving coil galvanometer falls from 25 divisions to 5 divisions when a shunt of 24 is applied. The resistance of galvanometer coil will be :
A galvanometer having coil resistance 10 shows a full scale deflection for a current of 3 mA. For it to measure a current of 8 A, the value of the shunt should be:
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A charge of 4.0 is moving with a velocity of 4.0 106 ms-1 along the positive y axis under a magnetic field B of strength (2 k) T. The force acting on the charge is x i N. The value of x is .
A proton moving with a constant velocity passes through a region of space without any change in its velocity. If E and B represent the electric and magnetic fields respectively, then the region of space may have : Choose the most appropriate answer from the options given below :
Two long, straight wires carry equal currents in opposite directions as shown in figure. The separation between the wires is 5.0 cm. The magnitude of the magnetic field at a point P midway between the wires is (Given : 0 = 4 10-7 T m A-1) [figure]
A current of 200 deflects the coil of a moving coil galvanometer through 60 . The current to cause deflection through 10 radian is :
The magnetic field at the centre of a wire loop formed by two semicircular wires of radii R1=2 m and R2=4 m, carrying current I=4 A as per figure given below is 10-7 T. The value of is . (Centre O is common for all segments) [figure]