A copper wire has a diameter of 0.5 mm and a resistivity of 1.6×10^−6 ohm-m. How much of this wire would be necessary to make a resistance of 10 ohm?

A copper wire has diameter 0.5 mm and resistivity of 1.6 xx 10^-8Omega m. What will be the length of this wire to make its resistance 10Omega ? How much does the resistance change if the diameter is doubled?

A potentiometer wire is of length 10 m and has a total resistance of 18 ohm. It carries a current of 120 mA. What length of it will be necessary to balance a cell of emf 1.5 volt ?

A battery of e.m.f 2V and internal resistance 1Omega is used to send a current through a potentiometer wire of length 200cm and resistance 4Omega . What length of the wire will be required to balance a cell of e.m.f 1.08V?

A potentiometer wire of length 100 cm has a resistance of 10 ohm. It is connected in series with a resistance and a battery of emf 2V and of negligible internal resistance. A source of emf 10mV is balanced against a length of 40 cm of the potentiometer wire. What is the value of the external resistance?

In a potentiometer experiment, it is found that no current passes through the galvanometer, when the terminals of a cell are connected across 50 cm of the potentiometer wire. If the cell is shunted by a resistance of 5 ohm, the balance point is found at 40 cm of the wire from the same end. Find the internal resistance of the cell.

A galvanometer gives full scale deflection with 0.2 mA. The resistance of its coil is 1000 ohms. How much shunt resistance is required to converted into an ammeter to measure currents upto a 2 amperers?