Same chapter3 marksDifficulty: Medium
Why does a class III lever always have a mechanical advantage less than one, and why is it still useful?
Machines
3 marksDifficulty: Medium
Classify levers into three orders, giving one example of each.
Original Khojo Papers practice question — not from a past board paper.
Answer
In a class I lever the fulcrum lies between the effort and the load, as in a pair of scissors. In a class II lever the load lies between the fulcrum and the effort, as in a wheelbarrow or a nutcracker. In a class III lever the effort lies between the fulcrum and the load, as in a pair of tongs or the human forearm.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
A class III lever always has a mechanical advantage less than 1, so it is used for speed and range of movement rather than for force.
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