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प्रश्न
Show that Lenz’s law is in accordance with the law of conservation of energy.
उत्तर
- The truth of Lenz’s law can be established on the basis of the law of conservation of energy.
- According to Lenz’s law, when a magnet is moved either towards or away from a coil, the induced current produced opposes its motion.
- As a result, there will always be a resisting force on the moving magnet.
- Work has to be done by some external agency to move the magnet against this resisting force.
- Here the mechanical energy of the moving magnet is converted into electrical energy which in turn, gets converted into Joule heat in the coil i.e., energy is converted from one form to another.
APPEARS IN
संबंधित प्रश्न
State Fleming’s right-hand rule.
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A generator has an e.m.f. of 440 Volt and internal resistance of 4000 hm. Its terminals are connected to a load of 4000 ohm. The voltage across the load is ______.
Induced current flows through a coil ______.
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.
