Year 9 Science · Unit 3 · Lesson 17
Apply Worksheet
Learning Goals
True or False? Fix the false ones
Circle T or F for each statement. If the statement is false, rewrite it correctly on the line below.
Voltage measures the rate at which electrons flow past a point in a circuit.
Correct it:
A voltmeter must be connected in series with the component it is measuring across.
Correct it:
If a switch in a circuit is opened (broken), the bulb goes out completely.
Correct it:
Resistance opposes the flow of current in a circuit.
Correct it:
Real-world context
Mia builds a simple torch circuit for a school experiment: she connects a 1.5 V cell, a switch and a small light bulb using copper wires. When she closes the switch, the bulb lights up, but dimly. She wants to make it brighter. Her teacher reminds her that voltage, current and resistance all play a role in how bright a bulb shines.
(a) Explain what voltage, current and resistance each mean in Mia's torch circuit. Give a specific example of where each quantity applies.
(b) Suggest TWO changes Mia could make to her circuit to increase the brightness of the bulb. Explain the scientific reason for each change.
(c) Mia accidentally cuts one of the copper wires. Explain why the bulb goes out completely, even though the battery is still connected.
Wrap Up
In one sentence, what was the main idea of this lesson?