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Examples of class-III (third-type) levers Identify the device that operates as a third-type lever (effort between fulcrum and load). Choose the correct example.

Difficulty: Easy

Handle of a hand pump
Hand wheel of a punching press
Lever of a loaded safety valve
A pair of tongs

Correct Answer: Handle of a hand pump

Explanation:

Concept
• Class-III (third-type) lever: effort lies between fulcrum and load (e.g., forearm, fishing rod, hand-pump handle).
• Safety-valve lever (with weight) and tongs are commonly modeled as class-I arrangements (fulcrum between load and effort); punching press hand wheel is not a lever example.

Final Answer
Handle of a hand pump

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