4456-43b9-8ae7-1c646782f501","label":null,"content":"Explain why it is more difficult to pedal when the dynamo is connected to the active headlight.","markscheme":"- Identifies that switching on the headlight completes the circuit, allowing an induced electric current to flow through the coil B1\n- Explains that this current produces a magnetic field that opposes the motion or rotation (in accordance with Lenz's law), meaning the cyclist must do more work or exert a greater force to maintain speed B1","marks":2,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"explain_dynamo","label":"Explain the dynamo","steps":[{"type":"text","order":1,"title":"Explain the current","content":"Switching on the headlight completes the circuit, so an induced current flows through the dynamo coil and the headlight. This earns **B1** because it identifies both the completed circuit and the induced current through the coil.","highlights":[{"text":"When the headlight is switched on, completing the circuit","location":"specification"}]},{"type":"text","order":2,"title":"Explain the opposing force","content":"The induced current produces a magnetic field that opposes the dynamo's rotation, in accordance with Lenz's law. The cyclist must therefore exert a greater force and do more work to maintain the **same constant speed**. This opposing magnetic effect earns the second B1 mark.","highlights":[{"text":"same constant speed","location":"specification"}]}]}],"generatedAt":"2026-07-22T11:36:20.768Z","modelVersion":"gpt-5.6-terra+diagrams-1","explanationVersion":"v3"},"options":[]}],"options":[],"explanation":null,"firstAttemptFullMarks":null},{"id":"522eaf43-ddf4-4f80-bd57-6c87fdb70873","revisionId":"4a82c037-83db-4259-a21c-54154a67e43e","questionNumber":null,"questionType":"LA","specification":"Figure 1 shows a copper coil connected to a sensitive centre-zero galvanometer.\n\n![Figure 1: Copper coil connected to a centre-zero galvanometer with a bar magnet nearby.](https://assets.mathsgenie.co.uk/aqa-qb/556d1142-a689-4d76-b519-cd7ff7f82485.png)","difficulty":5,"difficultyBand":"medium","totalMarks":3,"sourceTitle":null,"calculatorUse":null,"parts":[{"id":"bced08bf-9f74-469e-83c0-fcae822997c9","label":null,"content":"Explain the observations seen on the galvanometer when the North pole of the magnet is pushed into the coil, held stationary inside, and then pulled back out.","markscheme":"- Moving the magnet into the coil induces a potential difference (and current), causing the pointer of the galvanometer to deflect in one direction B1\n- When the magnet is stationary inside the coil, there is no change in magnetic flux linkage (no relative motion), meaning no current is induced, so the pointer returns to the centre-zero position B1\n- Pulling the magnet out of the coil causes a deflection of the pointer in the opposite direction because the direction of relative movement has reversed, which reverses the direction of the induced potential difference and current B1","marks":3,"order":0,"markingRubric":null,"explanation":{"methods":[{"id":"electromagnetic_induction","label":"Follow the magnet motion","steps":[{"type":"text","order":1,"title":"Push the magnet in","content":"As the North pole is pushed into the coil, the magnetic field through the coil changes. A potential difference is induced, so a current flows and the galvanometer pointer deflects in **one direction**.\n\nThis explanation earns the first mark: state both the induced potential difference/current and the resulting deflection.","highlights":[{"text":"North pole of the magnet is pushed into the coil","location":"specification"}]},{"type":"text","order":2,"title":"Hold it still","content":"When the magnet is held stationary inside the coil, there is no relative motion and therefore no change in magnetic flux linkage. No potential difference or current is induced, so the pointer returns to the centre-zero position.\n\nThat complete cause-and-effect chain earns the second mark.","highlights":[{"text"

Inducing current, generators and microphones

Question 5

Inducing current, generators and microphones Questions

Inducing current, generators and microphones

Question 5

Inducing current, generators and microphones Questions