A student investigates the principle of moments. A uniform metre rule is balanced on a pivot at its centre. A weight of 1.0 N is hung 0.20 m from the pivot on one side. The student then finds the distance d d\,d on the other side at which each of five different weights W W\,W balances the rule.
Table: The distance from the pivot at which each of five weights balances the rule
| Weight W W\,W in N | 0.50 | 1.00 | 2.00 | 4.00 | 5.00 |
|---|---|---|---|---|---|
| Distance d d\,d in m | 0.40 | 0.20 | 0.10 | 0.05 | 0.04 |
Calculate the moment of the 1.0 N weight about the pivot.
Use the data in the table to show that the rule is balanced for each of the five weights.
Explain why the rule must be balanced on the pivot before any weights are hung on it.
Give one way the student could reduce the effect of random error on the value of ddd.
40 exam-style questions on AQA GCSE Physics 5.4 Moments, levers and gears, covering 5.4 Moments, levers and gears. Each one has a worked solution and a mark scheme showing where the marks go.