Electromagnetic Induction » Exercise - 110. Eddy current may be appreciable in many cases. It heats metals and so a wastage of electrical energy noticed. This is undesirable in transformers, induction coil and choke coil. This can be minimised by using : (a) laminated cores in transformers (b) using bundles of soft iron rods in induction coils (c) using glass surfaces (d) all are false
Electromagnetic Induction » Exercise - 1 1. The mechanical energy spent by the external agency is converted into electrical energy stored in the coil. This relates to : (a) Ohm’s law (b) Coulomb’s law (c) Lenz’s law (d) Newton’s law of motion
Electromagnetic Induction » Exercise - 12. A magnetic field of induction 10 tesla acts along the axis of a coil of area 10 m2 with 20 turn. The magnetic flux linked with the coil is : (a) 1000 turn (b) 50 turn (c) 500 turn (d) 2000 turn
Electromagnetic Induction » Exercise - 19. If L1 and L2 are the self inductance of two coils then the mutual inductance between them is : (a) M = K (L1L2) (b) M = K √(L1/L2) (c) M = K√(L1L 2) (d) M = K(L1L2)2
Electromagnetic Induction » Exercise - 18. The dimensions of ‘self inductance’ and ‘magnetic flux’ are : (a) M L T –2 and M L 2 T –1 A –1 respectively (b) M L 2 T –2 A –2 and M L 2 T –2 A –1 respectively (c) M 2 L -1 T –1 and M 2 L 2 T –2 respectively (d) M T –2 A –1 and M 2 L T respectively