Lenz's law of electromagnetic induction states that
e.m.f. is induced in a circuit whenever there is a change in the magnetic flux linked with the circuit.
the induced current in a conductor is in such a direction as to oppose the change producing it
the magnitude of the induced e.m.f. in a circuit is proportional to the rate of change of the number of lines of force linking the circuit
a force is exerted on a current-carrying conductor in a magnetic Held
the induced charge is constant for a fixed change of flux.
Correct answer is B
No explanation has been provided for this answer.
5.0 x 107Ω-1cm-1
5.0 x 106Ω-1cm-1
2.0 x 106Ω-1cm-1
5.0 x 105Ω-1cm-1
2.0 x 106Ω-1cm-1
Correct answer is D
No explanation has been provided for this answer.
2.0 x 103 Ω
2.0 x 102 Ω
2.0 x 10-1 Ω
2.0 x 10-2 Ω
2.0 x 10-3 Ω
Correct answer is E
No explanation has been provided for this answer.
Which of the following is not a component of a d.c. electric motor?
Commutator
Field magnets
Slip rings
Armature
Carbon brushes
Correct answer is C
No explanation has been provided for this answer.
The main function of the mouth of a telephone is to convert sound energy into
heat energy
light energy
chemical energy
electrical energy
mechanical energy
Correct answer is D
No explanation has been provided for this answer.
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