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प्रश्न
Give an illustration of determining direction of induced current by using Lenz’s law.
उत्तर
- Move the bar magnet towards the solenoid with north pole pointing solenoid.
- When the Magnetic flux increases in the coil, an induced current is produced, and the coil becomes a magnetic dipole.
- According to Lenz law, induced current opposes the movement of the north pole towards coil.
(a)
(b)
(c)
- It is possible if end nearer to magnet becomes the north pole, then it repels the north pole of the magnet and oppose the movement of the magnet.
- The direction of induced current is found by the right-hand thumb rule.
- When a bar magnet is withdrawn, the nearer end becomes south pole which attracts the north pole of the bar magnet, opposing the receding motion of the magnet.
7. Direction of induced current can be found from Lenz law.
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संबंधित प्रश्न
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A) `(qR)/(Bm)`
B)`(qm)/(Br)`
C) `(qBR)/m`
D) `m/(qBR)`
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Draw and label the diagram of a simple D.C. motor.
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(c) How can you increase the speed of rotation of the motor?
State Fleming’s Right Hand Rule.
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Draw a labelled diagram to make an electromagnet from a soft iron bar. Mark the polarity at its ends in your diagram. What precaution would you observe while making it?
The condition for the praenomen of electromagnetic induction is that there must be a relative motion between ____________.
We can induce the current in a coil by ____________.
AB is a coil of copper wire having a large number of turns. The ends of the coil are connected with a galvanometer as shown. When the north pole of a strong bar magnet is moved towards end B of the coil, a deflection is observed in the galvanometer.
- State the reason for using galvanometer in the activity and why does its needle deflects momentarily when magnet is moved towards the coil.
- What would be observed in the galvanometer in a situation when the coil and the bar magnet both move with the same speed in the same direction? Justify your answer.
- State the conclusion that can be drawn from this activity.
Will there be any change in the momentary deflection in the galvanometer if number of turns in the coil is increased and a more stronger magnet is moved towards the coil?
OR
What is electromagnetic induction? What is observed in the galvanometer when a strong bar magnet is held stationary near one end of a coil of large number of turns? Justify your answer.
