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.
Mechanical Engineering
Machine Design
Difficulty: Easy
Choose an option
-
AHandle of a hand pump
-
BHand wheel of a punching press
-
CLever of a loaded safety valve
-
DA pair of tongs
Answer
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 AnswerHandle of a hand pump