A student investigates how the electrical power of different model appliances affects the current drawn when operating at a constant alternating potential difference of 12 V12\text{ V}12 V.
They set up the circuit shown below:
Describe a method the student could use to safely collect the data needed to plot a graph of current (yyy-axis) against power (xxx-axis) for a range of different model appliances.
Which of the following statements correctly describes the graph of current (yyy-axis) against power (xxx-axis) for these appliances under a constant operating potential difference?
- A: A straight line with a negative gradient.
- B: A curve that increases to a maximum and levels off.
- C: A straight line passing through the origin with a constant positive gradient.
- D: A curve starting from the origin with an increasing gradient.
The student's teacher points out that real domestic appliances operate on the UK mains supply (230 V230\text{ V}230 V). Explain why a 13 A13\text{ A}13 A current flowing through a mains-powered appliance is associated with a severe electrical shock hazard, whereas a 13 A13\text{ A}13 A current flowing in the student's 12 V12\text{ V}12 V model circuit is safe to touch.
Domestic uses and safety Questions
Practise AQA GCSE Physics Domestic uses and safety with exam-style questions for Foundation and Higher tier. 13 questions covering Direct and alternating potential difference and Mains electricity, matched to the AQA GCSE Physics (8463) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.