A system S consists of two coils A and B. The | vedclass

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(A) When the system is heated,the resistance of the coils increases due to the rise in temperature. Since the coil $A$ is connected to a source,the in

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The two coils show attraction.

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(A) When the system is heated,the resistance of the coils increases due to the rise in temperature. Since the coil $A$ is connected to a source,the increase in its resistance causes the current $I$ in coil $A$ to decrease steadily. According to Faraday's law of electromagnetic induction,a changing current in coil $A$ produces a changing magnetic flux through coil $B$. This changing magnetic flux induces an electromotive force (emf) and consequently an induced current in coil $B$. According to Lenz's law,the induced current in coil $B$ will flow in such a direction as to oppose the cause of its production,which is the decrease in current in coil $A$. To oppose the decrease in current,the induced current in coil $B$ will flow in the same direction as the current in coil $A$. Two parallel coils carrying currents in the same direction attract each other. Therefore,the two coils show attraction.

$A$ system $S$ consists of two coils $A$ and $B$. The coil $A$ carries a steady current $I$. The coil $B$ is suspended nearby as shown in the figure. If the system is heated,so as to raise the temperature of the two coils steadily,then:

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