Year 7 Science · Unit 3 · Lesson 9
Apply Worksheet
Learning Goals
Order the steps
Number the steps from 1 to 6 to show the correct order for using a spring scale to measure the friction force between a wooden block and a table surface. Step 1 = what you do first. The steps are shuffled — put them in the right sequence.
| Order | Step |
|---|---|
| Pull the spring scale horizontally at a slow, constant speed — keep the pull steady and even. | |
| Record the reading from the scale in your results table. Repeat at least three times to check for consistency. | |
| Read the scale when the pointer is steady and the block is moving at constant speed — that reading equals the friction force. | |
| Zero the spring scale by checking that the pointer sits exactly at 0 N before attaching anything. | |
| Place the wooden block on the table surface and attach the spring scale hook to the loop at the front of the block. | |
| Hold the spring scale horizontally in line with the direction of movement — never at an angle. |
Read the graph
The bar chart below shows the extension of a spring (in mm) when different forces are applied. Study the graph carefully, then answer the questions.
Data: Simulated spring extension data following Hooke's Law (10 mm/N), typical of a laboratory spring scale used in Australian Year 7 classrooms.
(a) Describe the pattern shown by the bars in the graph. What happens to the spring extension each time the force increases by 1 N?
(b) Using the pattern, predict what the spring extension would be at 6 N. Show your reasoning.
(c) What is the name of the scientific law that this graph demonstrates? Explain in your own words what this law says about springs.
Wrap Up
In one sentence, what was the main idea of this lesson?