Physics Practice: Current Electricity (Mock Test 3 - Advanced)
1. A cell of e.m.f. $\epsilon$ and internal resistance $r$ is connected to an external resistance $R$. The current $I$ in the circuit is maximum when:
2. Two wires of the same material have lengths in the ratio $1:2$ and areas of cross-section in the ratio $2:3$. The ratio of their resistances is:
3. When a current $I$ flows through a resistance $R$ for time $t$, the electrical energy dissipated as heat is:
4. A high resistance voltmeter is connected across the terminals of a cell in an open circuit. It measures:
5. Which of the following graphs represents an Ohmic conductor?
6. If the temperature of a metallic conductor increases, its resistance ________ and its resistivity ________.
7. A circuit consists of a $12\text{V}$ battery and two resistors of $3\Omega$ and $6\Omega$ in series. The current flowing through the $6\Omega$ resistor is:
8. Superconductors are materials that have ________ resistance at very low temperatures.
9. The "lost volt" in a circuit is numerically equal to:
10. To measure the potential difference across a resistor, a voltmeter must always be connected in: