Understanding how to approach exam questions helps to boost exam performance. Questions will include short answer, structured, data response and extended response questions.

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Do not forget to take a ruler and calculator into the exam.

Maths questions often start with the command words like 'calculate', 'determine', 'estimate' and 'measure'. They will then include a blank space for you to show your working.

When an answer to a maths question is marked:

- full marks are given for the right answer (but it is wise to show your working so you can check your answer)
- marks are given for working, including substitution and rearrangement
- errors carried forward are taken into account

Errors carried forward are related to what happens if a later answer depends on an earlier answer, and you get the earlier one wrong. You could still get full marks in the later answer if your working is correct but you use the incorrect earlier answer.

If your answer has many decimal places or figures, make sure you give it to an appropriate number of decimal places or significant figures. You may be asked to give units. This may earn you an additional mark, so do not forget to check whether you need to do this.

Some maths questions might ask you to plot or complete a graph or table. When you draw a graph, make sure you:

- plot each point accurately
- draw a best-fit straight line or curve

You may be given a grid with axes and scales already given. Sometimes you may be given an empty grid for you to supply your own axes. When you do this:

- put the independent variable on the x-axis and the dependent variable on the y-axis
- make sensible scales so that the plotted points cover at least 50% of the area of the graph
- label the axes with their quantity and unit, eg time(s)

*These questions have been written by Bitesize consultants as suggestions to the types of questions that may appear in an exam paper.*

- Question
The table shows the power rating and working current for three electrical appliances.

Each of the appliances uses the 230 volts mains.

Appliance Power (W) Current (A) Cooker 6,210 27 Laptop 40 Fridge freezer 1.4 **a)**Recall an equation to find the missing values in the table.**[3 marks]****b)**Which one of the three appliances is not connected using a 3-pin plug. Explain your answer.**[2 marks]****c)**One of the appliances does not need an earth wire connection. Which one, and why?**[2 marks]****a)**[1]P: Fridge freezer is 322 W [1]

I: Laptop is 0.17 A [1]

Appliance Power (W) Current (A) Cooker 6,210 27 Laptop 40 **0.17**Fridge freezer **322**1.4 **b)**The cooker [1] because its current is much greater than the maximum 13 A fuse for a 3-pin plug [1].**c)**The laptop because it is double insulated/has a plastic case [1]. The other two have metal cases so they require an earth connection [1].

- Question
Electric current flowing through a wire is really a flow of electrons that have a certain amount of electrical charge measured in Coulombs, C. These electrons carry energy from a source around the circuit. There are two equations you need to recall that include electrical charge, Q. Use these equations to answer the following:

**a)**A current of 2 A flows in a circuit that contains a single lamp, calculate the amount of charge that passes through the lamp in 3 s.**[2 marks]****b)**Calculate the number of electrons, each with a charge of 1.6 × 10^{-19}C, that pass through the lamp in 1 s.**[2 marks]****c)**This current is supplied by a 12 V battery. Calculate the energy transferred to the lamp.**[1 mark]****d)**Another identical lamp is added in series to this circuit. Describe the effect on:**i)**The voltage across the original lamp.**[1 mark]****ii)**The flow of electrons through the circuit.**[1 mark]****a)**[1][1]

**b)**Number of electrons = 6 ÷ (1.6 × 10^{-19}) [1]= 3.75 × 10

^{19}in 3 sIn 1 s we need to divide this by 3, so we have 1.25 × 10

^{19}electrons passing. [1]**(c)**[1]

**d) i)**It will halve to 6 V [1]**ii)**The number of electrons flowing each second will reduce [1]