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The expression for magnetic induction inside a solenoid of length L, carrying a current i and having N number of turns are

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Important Questions on Electromagnetic Induction and Alternating Currents

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction

Describe the magnetic field produced by a solenoid carrying current.

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
State right hand thumb rule.
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
What is a solenoid? How is it different from a permanent magnet?
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction

Kunal draws magnetic field lines close to the axis of a current carrying circular loop. As he moves away, towards the centre of the circular loop, he observes that the lines keep on diverging. How will you explain his observation?

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
The magnetic field inside a long straight current carrying solenoid :
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction

Electricity and magnetism are linked to each other.
Why does a current carrying solenoid when suspended freely rest along a north-south direction?

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction

Observe the given figure of Fleming' s Right Hand Rule and write the labels of A and B correctly.

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
A power transmission line feeds input power at 2300 V to a step down transformer with its primary windings having 4000 turns. The output power is delivered at 230 V by the transformer. If the current in the primary of the transformer is 5 A and its efficiency is 90 %, the output current would be:
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction

The diagram below shows a magnetic needle kept just below the conductor AB which is kept in the North-South direction.

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i) In which direction will the needle deflect when the key is closed?

ii) Why is the deflection produced?

iii) What will be the change in the deflection if the magnetic needle is taken just above the conductor AB?

iv) Name one device which works on this principle.

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
Draw the pattern of magnetic field lines produced around a current carrying straight conductor passing perpendicularly through a horizontal cardboard. State and apply right-hand thumb rule to mark the direction of the field lines. How will the strength of the magnetic field change when the point where magnetic field is to be determined is moved away from the straight conductor? Give reason to justify your answer.
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction

The diagram shows a current carrying wire passing through the centre of a square card board. The magnetic field at points A, B  and C is:

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
Which of the following is most suitable for the core of electromagnets?
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
A long solenoid has 1000 turns. When a current of 4 A flows through it the magnetic flux linked with each turn of the solenoid is 4×10-3 Wb. The self-inductance of the solenoid is:
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
What is a Solenoid? Draw the magnetic lines of force around a current-carrying solenoid. Also, throw some light on the use of solenoid.
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
The self induced emf of a coil is 25 volts. When the current in it is changed at uniform rate from 10 A to 25 A in 1 s , the change in the energy of the inductance is:
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
A long solenoid has 500 turns. When a current of 2 A is passed through it, the resulting magnetic flux linked with each turn of the solenoid is 4×10-3 Wb, then self-inductance of the solenoid is
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
A small circular loop of wire of radius a  is located at the centre of a much larger circular wire loop of radius b. The two loops are in the same plane. The outer loop of radius b carries an alternating current I=I0cos⁡ωt. The emf induced in the smaller inner loop is nearly:
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction

What is a solenoid? Can you determine the North and South poles of a current-carrying solenoid with the help of a bar magnet? Explain.

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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
The magnetic field inside a solenoid is
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Physics>Electricity and Magnetism>Electromagnetic Induction and Alternating Currents>Self and Mutual Induction
A short solenoid (length l and radius r with n turns per unit length) lies well inside and on the axis of a very long, coaxial solenoid (length L, radius R and N turns per unit length, with R>r). Current I follows in the short solenoid. Choose the correct statement.