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प्रश्न
Statement 1 : Electric current ( flow of electrons ) creates heat in the resistor.
Statement 2 : Heat in the resistor is created according to the rule of energy conservation.
Explain Statement 1 with the help of Statement 2.
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उत्तर
i. When electrons flows through the resistor (during flowing electric current) electron possesses kinetic energy.
ii. During the flow of electron there is decrease in kinetic energy of electrons due to collision on atoms, ions and molecules.
iii. According to the law of conservation of energy decrease in kinetic energy gets converted into heat.
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SFEU
Your teacher has shown you the following activity.

Activity: Teacher has wound a long insulated piece of wire around an iron nail in the form of a coil. Free ends of the wire are connected to a cell through a switch as shown in the following figure. The current is switched on and some pins are placed near the ends of the nail.
Write down any three questions that come to your mind about this activity.
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