The lamp is off. Explain why the lamp lights when the switch is closed.
[2 marks]
.3
When the switch is closed, the reading on X is 0.20 A.
Calculate the charge that flows through the lamp in 60 s.
[2 marks]
6 marksFoundation and HigherRequired practical 156.2.1.3
A student measures the resistance of a length of wire. The diagram shows the correct circuit.
RAV
.1
How is the voltmeter connected to the wire R?
[1 mark]
.2
The voltmeter reads 3.0 V. The ammeter reads 150 mA.
Calculate the resistance of the wire.
[3 marks]
.3
The student switches the circuit off between readings. Suggest why.
[2 marks]
6 marksFoundation and HigherRequired practical 166.2.1.4, 6.2.1.3
A student investigates how the current through a component depends on the potential difference across it. They reverse the connections to get the negative values. The graph shows the results.
Explain why the graph is a curve and not a straight line.
[3 marks]
.3
Determine the resistance of the component when the potential difference is 6.0 V.
[2 marks]
6 marksFoundation and HigherRequired practical 156.2.1.3
A student is given a battery, an ammeter, a voltmeter, a metre rule, crocodile clips and a long piece of constantan wire taped to the metre rule.
Plan an investigation into how the length of the wire affects its resistance.
[6 marks]
7 marksFoundation and Higher6.2.1.2, 6.2.1.3
A sensor carries a steady current of 0.040 A for 3.0 minutes. The potential difference across it is 6.0 V.
.1
Calculate the charge passing through the sensor.
[3 marks]
.2
Calculate the resistance of the sensor.
[2 marks]
.3
Explain why the current entering and leaving the sensor is the same.
[2 marks]
6 marksFoundation and HigherRequired practical 166.2.1.4, 6.2.1.3
During an I-V investigation a filament lamp takes 0.20 A at 1.0 V and 0.50 A at 6.0 V.
.1
Calculate the resistance at 1.0 V.
[2 marks]
.2
Calculate the resistance at 6.0 V.
[2 marks]
.3
Explain the change in resistance as the potential difference increases.
[2 marks]
5 marksFoundation and HigherRequired practical 156.2.1.3
A student measures the resistance of 0.20 m, 0.40 m and 0.60 m of one uniform wire. Values are 1.6 Ω, 3.2 Ω and 5.6 Ω. The 0.60 m measurement is made after current has flowed for several minutes.
.1
Use the first two results to calculate the expected resistance of 0.60 m of wire at the original temperature.
[2 marks]
.2
Evaluate the final result and suggest how to improve the investigation.