The specific resistance of copper, silver and constantan are 1.78 x 10^-6 Ω cm, 10^-6 Ω cm and 48 x 10^-6 Ω cm respectively.

(i) Identify the best conductor.

(ii) Give reason for your answer above.

The current flowing through a conductor is 2 A at 50 V and 3 A at 60 V. Identify whether the conductor is ohmic or not.

Emf of a cell is …………… the terminal voltage when cell is not in use, while …………… the terminal voltage when cell is in use.

1. greater than, smaller than
2. smaller than, greater than
3. equal to, greater than
4. equal to, smaller than

Current drawn from the cell :

1. I = ε[R+r]
2. I = $\dfrac{{\varepsilon}}{{(R + r)}}$
3. I = εR
4. I = $\dfrac{{E}}{{(r)}}$