Fig 3.18 below shows the use of a lever.
(a) State the principle of moments as applied to the above lever.
(b) Give an example of this class of lever.
(c) If FA = 10 cm, AB = 500 cm calculate: (i) the mechanical advantage and (ii) the minimum effort required to lift the load.
(a) The principle of moments: Moment of the load about the fulcrum=moment of the effort about the fulcrum
FB × Load = FA × Effort
(b) Sugar tongs the example of this class of lever.
(c) Given: FA = 10 cm, AB = 500 cm, BF = 500 + 10 = 510 cm.
The mechanical advantage
M.A = `"AF"/"BF"`= `10/510`= `1/51`
The minimum effort required to lift the load
Effort = `"Load "/"M.A"`=`50/(1/51)` = 2550 N