# Practical questions

You will complete 21 required practical activities if you are studying GCSE Combined Science: Trilogy. You could be asked questions about the apparatus, methods, safety precautions, results, analysis and evaluation of these experiments.

There will be a number of different types of practical based questions. Some will be on the set required practicals, some will cover the working scientifically terms and some will be on other science practicals which you might have done in class. Use all the information given in the question particularly any diagrams to help you understand what the question is about.

This page contains AQA material which is reproduced by permission of AQA.

## Sample question 1 - Foundation

Question

A student sets up a circuit like the one shown below:

Describe how the student could use her circuit to investigate how the current through a filament lamp affects its resistance. [4 marks]

The ammeter is used to measure current [1]. The voltmeter is used to measure potential difference [1]. The resistance of the variable resistor is adjusted to change the current in the circuit or the potential difference across the filament lamp [1]. The resistance of the lamp can be calculated using [1].

## Sample question 2 - Foundation and Higher

Question

A resistor is a component that is used in an electric circuit.

Describe how a student would use the circuit to take the readings necessary to determine the resistance of the resistor. [6 marks]

1. switch on the circuit
2. read both the ammeter and voltmeter
3. adjust the variable resistor to change the current
4. take new readings from the ammeter and voltmeter
5. draw a voltage-current graph
6. use the equation: resistance = voltage ÷ current

[6]

For this type of question, a list of clear and logical instructions is needed. The answer should be written so that someone can easily follow the set of instructions, even if they have not done the experiment before.

## Sample question 3 - Higher

Question

When some metals are heated the resistance of the metal changes.

The equipment for investigating how the resistance of a metal changes when it is heated is shown in the diagram below:

Describe an investigation a student could do to find how the resistance of a metal sample varies with temperature. The student uses the equipment shown.

• how the student should use the equipment
• the measurements the student should make
• how the student should use these measurements to determine the resistance
• how to make sure the results are valid

[6 marks]

1. read the voltage and current and record for the starting temperature
2. apply heat
3. remove the source of heat and stir before taking readings
4. read the voltage and current for at least three different temperatures
5. plot a graph of resistance against temperature
6. determine R from: V ÷ I

[6]

For this type of question, a list of clear and logical instructions is needed. The answer should be written so that someone can easily follow the set of instructions, even if they have not done the experiment before.