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Question
The diagram shows the use of a lever.
- State the principle of moments as applied to the above lever.
- Which class of lever is this? Give an example of this class of lever.
- If FA = 100 cm, AB = 90 cm, calculate the minimum effort required to lift the load.
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Solution
(i) Sum of the clockwise moments about the fulcrum is equal to the sum of the anti-clockwise moments about the fulcrum.
(ii) Lever of class III,
Example: forceps or a pair of tongs.
(iii) E × 100 = 190 × 20
∴ E = 38 N.
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