The sliding contact C is at one fourth of the length of the potentiometer wire (AB) from A as shown in the circuit diagram. If the resistance of the wire AB is R0, then the potential drop (V) across the resistor R is
Two resistors of resistance, 100 $$\Omega$$ and 200 $$\Omega$$ are connected in parallel in an electrical circuit. The ratio of the thermal energy developed in 100 $$\Omega$$ to that in 200 $$\Omega$$ in a given time is
A copper wire of length 10 m and radius $$\left( {{{{{10}^{ - 2}}} \over {\sqrt \pi }}} \right)$$ m has electrical resistance of 10 $$\Omega$$. The current density in the wire for an electric field strength of 10 (V/m) is
A capacitor of capacitance C = 900 pF is charged fully by 100 V battery B as shown in figure (a). Then it is disconnected from the battery and connected to another uncharged capacitor of capacitance C = 900 pF as shown in figure (b). The electrostatic energy stored by the system (b) is