Answer to AQA GCSE Resistors - Science Worksheets

Answers to AQA GCSE Resistors

Practice Questions

1.State Ohm’s Law

Ohm’s law state that the current which flows through a resistor (component) is directly proportional to the potential difference across the resistor, providing that the temperature is constant.

2. Draw a data table to collect the data for the testing resistors experiment above

Potential difference (V)	Current (A)

3. Describe and explain the current-potential difference graph for a length of wire.

Starting at 0A, 0V. As the potential difference increases, so does the current, there is a directly proportional relationship. This is consistent with ohms law.

If the terminals are swapped, the same pattern is seen in reverse, this is shown in the bottom left part of the graph.

4.Describe and explain the current-potential difference graph for a bulb

Starting at 0A, 0V. As the potential difference increases, the current increases, but reaches a maximum value. This is because the filament wire in the bulb becomes hot and its resistance increases, which limits the current. As a result, this is a non ohmic conductor.

If the terminals are swapped, the same pattern is seen in reverse, this is shown in the bottom left part of the graph.

5. Describe and explain the current-potential difference graph for a diode.

A diode has a low resistance direction and a high resistance direction.

Starting at 0A, 0V. As the potential difference increases, at a minimum potential difference in the low resistance direction a current will flow, causing the IV graph to up upwards.

If the terminals are switched so the potential difference would be applied in the high resistance direction for the diode, regardless of the potential difference applied, no current would flow.