A student investigates a steel spring. She measures the length of the spring, then she hangs different weights from the spring. She measures the length of the spring for each different weight.
The table shows her results.
| Weight / N\text{N}N | Length of spring / mm\text{mm}mm |
|---|---|
| 0.0 | 150 |
| 3.0 | 168 |
| 6.0 | 186 |
| 9.0 | 204 |
A weight of 5.0 N is hung from the spring.
What is the extension of the spring?
18 mm18\text{ mm}18 mm
30 mm30\text{ mm}30 mm
150 mm150\text{ mm}150 mm
180 mm180\text{ mm}180 mm
245 exam-style questions on CIE IGCSE Physics 1.5 Forces, covering 1.5.1a Forces, resultant force and motion, 1.5.1b Load–extension graphs and the spring constant, 1.5.1c Friction and drag, 1.5.1d Force, mass and acceleration, 1.5.1e Motion in a circular path, 1.5.2a Moment of a force, 1.5.2b Principle of moments and equilibrium, and 1.5.3 Centre of gravity and stability. Each one has a worked solution and a mark scheme showing where the marks go.