An electromagnetic mechanism for a safety gate uses a solenoid to pull an iron plunger against a spring to open the latch.
Explain why the plunger must be made of iron rather than brass.
When the solenoid is activated, a force of 3.60 N3.60\text{ N}3.60 N is applied to the spring, causing it to compress by 1.80 cm1.80\text{ cm}1.80 cm. Calculate the spring constant of the spring in N/m\text{N/m}N/m.
State two modifications to the solenoid or circuit that would increase the magnetic force on the plunger.
Practise AQA GCSE Physics The motor effect with exam-style questions for Foundation and Higher tier. 25 questions covering Electromagnetism, Fleming's left-hand rule (HT only), Electric motors (HT only), and Loudspeakers (physics only) (HT only), 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.