Electric Circuits: Resistance, Series, Parallel and Safety
Electric Circuits: Resistance, Series, Parallel and Safety is one of 9 topics in the Grade 9 Natural Sciences CAPS syllabus, covered across 3 lessons on Study Vault. Below are real practice questions from this topic with full worked answers.
Sample practice questions
Easy
1. What is a battery?
A group of cells connected together
A single resistor
A type of circuit breaker
A device that only produces heat
Answer: A group of cells connected together — A battery is a group of cells that are connected together, while a single cell is itself a source of electricity.
Easy
2. What happens to a conductor when current passes through it, due to resistance?
It heats up, because some electrical energy is lost as heat
It always cools down
It becomes magnetic permanently
It stops conducting electricity entirely
Answer: It heats up, because some electrical energy is lost as heat — Conductors heat up when current passes through them, because some electrical energy is "lost" or "wasted" as heat due to resistance.
Medium
3. Which is more resistant: a thin wire or a thick wire, if both are made of the same material and length?
Answer: a thin wire — Thinner wires have more resistance than thicker wires, because a thicker wire gives electrons more room to flow.
