The graphs show how the current in a component changes with the voltage applied across the component.

Which graph matches the component

The graphs show how the current in a component changes with the voltage applied across the component.

Which graph matches the component

A student investigates resistors connected in series in an electrical circuit.

The student has:         

a 3.0 V battery        

a 22 Ω resistor         

a resistor marked X.The student does not know the value of the resistor marked X.

The student decides to measure the potential difference (voltage) across resistor X.

Figure 15 shows the circuit that the student connected.

The circuit is connected incorrectly. Describe how the student should correct the mistake.

A wier in a circuit carries a current of 0.9A. Calculate the quantity of charge that flows through the wire in 50s. State the unit of charge with your answer.

Charge = current x time

A student sets up an experiment to measure the potential difference (voltage) across a filament lamp.

She changes the current through the lamp.

The diagram shows the circuit she used.

Calculate the resistance of the lamp when the current is 0.44 A and the potential difference is 10.0 V

R = V/I

Draw a circuit diagram you could use to investigate the relationship between potential difference, current and resistance for a filament lamp.

A resistor is connected to a power supply. The resistor becomes warm while there is a current in it.

Explain why the resistor becomes warm.

Figures 21 and 22 show different voltages that can be applied across a wire

Explain which of the voltages in the figures 21 and 22 cause an a.c. current in the wire.