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Question
Fig 3.17 below shows a lever in use.
(a) To which class of lever does it belong?
(b) If FA = 80 cm, AB = 20 cm, find its mechanical advantage.
(c) Calculate the value of E.
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Solution
(a) This is a class II lever.
(b) Given: FA=80 cm, AB = 20 cm, BF= FA+AB=100cm
Mechanical advantage M.A = `"๐ต๐น"/"๐ด๐น"`= `100/80` = 1.25
(c) Effort (E) = `"๐ฟ๐๐๐ (๐ฟ)"/"๐.๐ด"` = `5 /1.25` = 4 ๐พ๐๐
RELATED QUESTIONS
The lever for which the mechanical advantage is less than 1 has :
A 4 m long rod of negligible weight is to be balanced about a point 125 cm from one end and a load of 18 kgf is suspended at a point 60 cm from the support on the shorter arm.
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- If a weight 5 kgf is kept to balance the rod, find its position.
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