KS4 Physics Module 4
D:\279178046.doc 08/12/20
Moments and Levers
The turning effect of a force is called a “moment”.
You may have heard of “leverage” or “torque” – they’re the same thing.
We work it out using Moment = Force x Distance .
The force must be in Newtons (N), the distance in metres (m), and we measure
moments in “Newton Metres”(Nm)
Answer these :-
2 metres
1. What is the moment of this force ?
6 Newtons
pivot
1.5 metres
2. What is the moment of this force?
3 Newtons
pivot
3. What is the length of this lever if
the moment is 8 Nm ?
?? metres
2 Newtons
pivot
For a see-saw to balance, the moments on each side must be the same.
For each of these, write “balanced” or “unbalanced” :
4.
10kg
1m
6.
20kg
8m
5kg
2m
15kg
10kg
5.
15kg
12m
2kg
7.
8m
3kg
8m
11m
5m
All of these see-saws are balanced. Work out the missing number for each one.
8.
40kg
10m
10.
??kg
15m
50kg
??
m
15kg
3m
7kg
9.
??kg
10m
11.
12kg
140m
5m
28kg
??m