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P4 General Studies: Closed Circuits, Conductors and Insulators (Paper 3: challenge)
Tutor Prep Guide · parts of a closed circuit, conductors against insulators, series against parallel, adding up battery voltage, and electrical safety
P4 General Studies: Closed Circuits, Conductors and Insulators (Paper 3: challenge)
Paper three moves on to circuit symbols, short circuits, power and resistance, all checked in Python.
Direct answers Remember one line: power is voltage times current, resistance is voltage over current.
01 Paper details (check answers afterwards)
| Item | Detail |
|---|---|
| Questions | 10 |
| Suggested time | 20 |
| Difficulty mix | Foundation 3 · Intermediate 3 · Challenge 3 · Error redo 1 |
| Chapter | Chapter: P4 General Studies: Closed Circuits, Conductors and Insulators |
| Level | parts of a closed circuit, conductors against insulators, series against parallel, adding up battery voltage, and electrical safety |
02 Questions (10 items)
- FoundationWhat does a pair of parallel lines, one long and one short, mean in a circuit diagram?
- FoundationWhat is a short circuit and why is it dangerous?
- FoundationWhat is the job of a fuse or a circuit breaker?
- IntermediateA bulb runs on 3 V with a current of 0.2 A. What is its power?
- IntermediateA circuit has 24 V across it and a current of 0.5 A. What is the resistance?
- IntermediateTwelve 1.5 V cells in series give what voltage?
- ChallengeA bulb on 6 V draws 0.3 A. What is the power?
- ChallengeAnother bulb uses 4.5 V at 0.4 A. What is its power?
- ChallengeFour 1.5 V cells in series, with one reversed. What is the total voltage?
- Error redoIs it true that a longer copper wire has less resistance?
03 Answers and one-line notes
| # | Answer | One-line note |
|---|---|---|
| 1 | A battery, with the long line as positive and the short line as negative. | Symbols show the kind of part, not its real size. |
| 2 | Current returns straight to the battery without passing the bulb, so wires overheat and may catch fire. | With almost no resistance, the current becomes very large very quickly. |
| 3 | It cuts the circuit when the current is too large, so the wiring cannot overheat. | A fuse gives itself up to keep the whole house safe. |
| 4 | 0.60 W. | Power is voltage times current, so 3 times 0.2 gives 0.60 W. |
| 5 | 48.0 ohms. | Resistance is voltage over current, so 24 divided by 0.5 gives 48.0. |
| 6 | 18.0 V, far beyond a safe level to test by hand. | 1.5 times 12 gives 18.0 V. |
| 7 | 1.80 W. | 6 times 0.3 gives 1.80 W. |
| 8 | 1.80 W, the same as the last question. | 4.5 times 0.4 gives 1.80 W: same power from a different voltage and current. |
| 9 | 4.5 V. | 1.5 plus 1.5 plus 1.5 minus 1.5 gives 4.5 V. |
| 10 | No, the longer the wire, the greater the resistance, so the bulb dims. | Resistance grows with length and falls with thickness. |
04 What to do after marking
- After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
- Repeat the same item two days later; move to the next paper only when both attempts are correct.
- Parents only need the answer and note columns; there is no need to explain every item.
Paper four clears the conductor, insulator and battery direction misconceptions.Tutor Registration →
Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.