A student is investigating the extension of a spring.
She measures the unstretched length l0l_0l0 of the spring to be 20 mm20\text{ mm}20 mm. She then hangs a range of loads LLL on the spring and measures the new length lll each time. She calculates the extension eee of the spring using e=l−l0e = l - l_0e=l−l0.
The table below shows her measurements:
| Load L/NL / \text{N}L/N | [Heading 1] | [Heading 2] |
|---|---|---|
| 0.00.00.0 | 202020 | 000 |
| 0.50.50.5 | 222222 | |
| 1.01.01.0 | 242424 | |
| 1.51.51.5 | 262626 | |
| 2.02.02.0 | 282828 | |
| 2.52.52.5 | 313131 | |
| 3.03.03.0 | 353535 |
Complete the column headings by identifying the correct quantities and units for [Heading 1] and [Heading 2].
Calculate the missing values for the extension eee of the spring to complete the third column.
State whether the results support the suggestion that the extension of the spring is directly proportional to the load over the entire range of measurements. Justify your answer by referring to your calculated values.
Describe two precautions the student should take when positioning and reading the ruler to ensure the length measurements of the spring are as accurate as possible.
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.