Forces can cause objects to rotate around a pivot point. Moments, also called turning forces, are what cause this rotation. A seesaw is used as an example, where the pivot is in the center and it will tip up if more weight is placed on one side versus the other. To balance the seesaw again, equal weight needs to be placed on the other side so that the opposing moments are equal. Calculating a moment requires knowing the force being applied and the distance of that force from the pivot point, using the equation: moment = force x distance.

1. Getting the balance
right

2. video

4. pivot
n. the central point, pin,
or shaft on which a
mechanism turns or
oscillates

5. see-saw
n.
a long board that childre
n play on.
The board is balanced on
a central point.

6. level
adj.
having a flat,
horizontal surface

7. balance
n.a state where things
are
of equal weight or forc
e

8. distanc
e
n.
the amount of space b
etween two places

9. MOMENTS

10. MOMENTS
Forces can make objects turn if there is a pivot.
Think of a playground see-saw. The pivot is the
thing in the middle of it.

11. When no-one is on the see-saw it is level, but it
tips up if someone gets onto one end. Turning
forces around a pivot are called moments.

12. It is possible to balance the see-saw again if
someone else gets onto the other end and sits
in the correct place. This is because the turning
forces are balanced. We say the moments are
equal and opposite.

13. To work out a moment, we need to know two
things:
1. the distance from the pivot that the
force is applied.

14. 2. the size of the force applied

15. This is the equation for working out a
moment:
moment = force ×
distance

16. Getting the balance
right

17. You will get these following
things,,,
- string
- chopsticks
- things for hanging
- tape

18. Use those things to make
mobiles that balance and
hang properly

20. thanks