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Design & Technology

Mechanisms

Levers: 2

On a pair of tweezers, the Fulcrum is at the join between the two pincers. The Effort is applied in the middle, and the Load is between the pincers

A class 3 lever does not have the mechanical advantage of class-one levers and class-two levers, so examples are less common. The effort and the load are both on the same side of the fulcrum, but the effort is closer to the fulcrum than the load, so more force is put in the effort than is applied to the load. These levers are good for grabbing something small, fiddly or dirty, or picking up something that could be squashed or broken if too much pressure is applied. The common example of class 3 levers is a pair of barbeque tongs or a pair of tweezers.

Learn the position of load, effort and fulcrum for each class of lever. Linking it to a practical example will help you to remember them.

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