Two wires X and Y have the same resistivity but their cross-sectional area are in the ration of \(2:3\) and lengths are in ratio of \(1:2\). They are first connected in series and then connected in parallel to d.c. source. Find: the ration of the drift speed of the electrons in the two wires for two cases.
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The current through a wire depends upon time as \(I=I_{0}+\alpha.t\), where \(I_{0}=10A\) and \(\alpha=4As^{-1}\). Find: the charge that flows across a section of the wire in \(10Seconds\).
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Calculate: the steady state current through \(2\Omega\) resistor in the given circuit. The internal resistance of the battery is negligible and \(C=2\mu C\).
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One meter long metallic wire is broken into two unequal parts X and Y. The part X is uniformly extended into another wire Z. The length of the wire Z is twice as of the wire X and the resistance of Z is equal to that of Y. Find: the ratio of the resistance of X and Z and also the ratio of lengths X and Y.
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the current through a conductor is \(1 Ampere\) when the temperature is \(0^{o}C\) and \(0.7 Ampere\) when the temperature is \(100^{o}C\). What would be the current when the temperature of of the conductor is \(1200^{o}C\)?
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A galvanometer together with an unknown resistance in series is connected across the two identical batteries each of \(1.5V\). When the batteries are connected in series, the galvanometer records a currents a current of \(1A\) and when the batteries are in parallel, the current is \(0.6A\). What is the internal resistance of battery?
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A uniform wire of resistance R is shaped into a regular n sided polygon, where n is even number. Find: the equivalent resistance between (i) Opposite corners of the polygon. (ii) Adjacent corners of the polygon.
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Two cells of e.m.f.’s \(1V\), \(2V\) and internal resistance \(2\Omega\) and \(1\Omega\) respectively are connected (i) In series. (ii) In parallel. What should be the external resistance in the circuit so that the current through the resistance be the same in the two cases? In which case more heat is generated in the cells?
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A potentiometer wire has a length \(L\) and a resistance \(R_{o}\). It is connected to a battery and a resistance combination as shown in below figure. Obtain the expression for the potential drop per unit length of this potentiometer wire. What is the maximum e.m.f. of a ‘test cell’ for which one can get a ‘balanced point’ on this potentiometer wire?
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A cell supplies a current \(I_{1}\) through a coil of resistance \(R_{1}\), a current \(I_{2}\) through a coil of resistance \(R_{2}\). What is the e.m.f. and internal resistance of the cell in terms of \(I_{1}\), \(I_{2}\), \(R_{1}\) and \(R_{2}\)?
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The resistance of \(R\Omega\) draws a current from a potentiometer. The potentiometer has a total resistance of \(R_{o}\Omega\). A voltage V is supplied to the potentiometer. Derive an expression for the voltage across R when the sliding contact is an the middle of the potentiometer.
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In the given meter bridge experiment, a student observed a balance point at the point J, where; AJ=l. Draw the equivalent wheatstone bridge diagram for this set up. The value of R and X are both doubled and then inter changed at the balance point position, how will be balanced point will get effected?
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A battery having a internal resistance \(r\left(=4\Omega\right)\) is connected to the network of resistances. What must be the value of R, so that maximum power delivered to the network? What is the maximum power?
