P3 General Studies: Home Electricity Safety (Paper 1 (basics))

2026-11-13

Tutor Prep Guide · conductors and insulators, power and electricity cost, series and parallel circuits, fuses and earth protection, and safe habits at home

Paper one covers the basics: conductors and insulators, wet hands and shocks, socket overload, and the power and cost conversions.

Direct answers　For each item write down the known voltage, current or power, put them into the formula, and then check whether the unit is watts, units or dollars.

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: P3 General Studies: Home Electricity Safety
Level	parts of a closed circuit, conductors against insulators, series against parallel, adding up battery voltage, and electrical safety

02　Questions (10 items)

FoundationWhich of these materials lets electricity pass through? Use copper wire, plastic, wood or glass as the choices.
FoundationWhy should wet hands never touch plugs or switches?
FoundationWhat can happen when too many high-power appliances share one socket?
IntermediateAn appliance runs at 220 V and draws 5 A. What is its power in watts?
IntermediateA 60 W lamp is used for 5 hours a day for 30 days. How many units of electricity does it use?
IntermediateWhat is the largest power a 13 A socket can carry at 220 V?
ChallengeTwo 10 ohm resistors are joined in series. What is the total resistance in ohms?
ChallengeA 2000 W electric kettle is used for half an hour. How many units of electricity does it use?
ChallengeIf one unit of electricity costs $1.2, what is the bill for 9.0 units?
Error redoA classmate says a live metal case is harmless because the current returns to the circuit by itself. What is wrong?

03　Answers and one-line notes

#	Answer	One-line note
1	Copper wire.	Metals are conductors that let current flow; plastic, wood and glass are insulators.
2	Water conducts electricity, so wet hands lower the resistance of the body and a shock becomes likely.	The water carries current into the body, which is far more dangerous than dry hands.
3	The current becomes too large, so the wire and socket overheat and a fire may start.	Every socket has a rated current, and going past it produces heat.
4	1100 W	Power is voltage times current: two hundred twenty times five gives 1100 W.
5	9.0 units	Sixty times five times thirty gives 9000 Wh, which is 9.0 units.
6	2860 W	Two hundred twenty times thirteen gives 2860 W, and anything above that is an overload.
7	20 ohms	In series the resistances add up: ten plus ten gives 20 ohms.
8	1.0 units	Two thousand times zero point five gives 1000 Wh, which is one unit.
9	$10.8	Nine times one point two equals 10.8.
10	The case must be earthed, because a person touching it sends current through the body to the ground, which can be fatal.	Current takes the path of least resistance, and a human body is one such path.

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.

After paper one, take paper two and sort out series against parallel in one pass.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.