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Sample of Experiment
Sample of Experiment
Sample of Experiment
Sample of Experiment
Experiment 1 (Lever Apparatus
Experiment 1 (Lever Apparatus
Experiment 1 (Lever Apparatus
Experiment 1 (Lever Apparatus))))
Lever Apparatus is designed for a student experiments regarding moment (of force) – torque in the
lever balance. Moment of force is the product of the distance of mass from the fulcrum point and
the weight.
[ Weight ] x [ Distance from the fulcrum point ] = Moment of force
Therefore when an anticlockwise moment equals a clockwise moment of the lever, the lever can
keep its balance horizontally.
Moment (anticlockwise) = Moment (clockwise)
Let’s set weight unit as 1w and set distance unit
as 1a.
In Fig.1, the right side of the lever has a weight
at position 4. Its moment of force is:
[Moment(clockwise)] = 4a x 1w = 4aw
The left side of the lever has 4 weights at position
1. Its moment is:
[Moment(anticlockwise)] = 1a x 4w = 4aw.
Therefore:
[Moment (clockwise)] = [ Moment (anticlockwise)]
[ Fig.1 ]
[ Fig.2 ]
In Fig.2, the right side of the lever has 3
weights at position 1, 1 weight at position 2,
and 2 weights at position 3. Its moment of
force is:
[Moment(clockwise)] = (1a x 3w) + (2a x 1w) +
(3a x 2w) = 3aw + 2aw + 6aw = 11aw
The left side of the lever has 1 weight at
position 2, 1 weight at position 3, and 1 weight
at position 6. Its moment of force is:
[Moment(anticlockwise)] = (2a x 1w) + (3a x
1w) + (6a x 1w) = 2aw + 3aw + 6aw = 11aw.
Therefore:
[Moment (clockwise)] =
[ Moment (anticlockwise)]
