# A-level Physics (Advancing Physics)/Resistance and Conductance/Worked Solutions

**1. The potential difference across a resistor is 4V, and the current is 10A. What is the resistance of the resistor?**

**2. What is the conductance of this resistor?**

**3. A conductor has a conductance of 2S, and the potential difference across it is 0.5V. How much current is flowing through it?**

I = 1A

**4. A graph is drawn of potential difference across an Ohmic conductor, and current. For every 3 cm across, the graph rises by 2 cm. What is the conductance of the conductor?**

**5. On another graph of potential difference and current, the graph curves so that the gradient increases as current increases. What can you say about the resistor?**

The resistor is not an Ohmic conductor.

**6. 3 resistors, wired in series, have resistances of 1kΩ, 5kΩ and 500Ω each. What is the total resistance across all three resistors?**

ΣR = (1 x 10^{3}) + (5 x 10^{3}) + 500 = 6500Ω = 6.5kΩ

**7. 2 conductors, wired in parallel, have conductances of 10S and 5S. What is the total resistance of both branches of the parallel circuit?**

**8. The circuit above is attached in series to 1 10Ω resistor. What is the total conductance of the circuit now?**