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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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(a) This is a class II lever.
(b) Given: FA=80 cm, AB = 20 cm, BF= FA+AB=100cm
Mechanical advantage M.A = `"ЁЭР╡ЁЭР╣"/"ЁЭР┤ЁЭР╣"`= `100/80` = 1.25
(c) Effort (E) = `"ЁЭР┐ЁЭСЬЁЭСОЁЭСС (ЁЭР┐)"/"ЁЭСА.ЁЭР┤"` = `5 /1.25` = 4 ЁЭР╛ЁЭСФЁЭСУ
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(i) To which class of lever does it belong?
(ii) If FA = 40 cm, AB = 60 cm, then find the mechanical advantage of the lever.
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