A right angled bell-crank is designed to raise a load of 5kN at short arm whose length is 100mm. Longer arm is of length 500mm. Calculate the reaction or force acting on the fulcrum.

A)
6.1
B)
6.8
C)
5.1
D)
5.8

Correct Answer : Option (C) :   5.1


Explanation : Force required for raising at longer end is found by F ₂xl₂ =F₁ xl₁. Reaction at fulcrum is √ (F₁²+F₂²) as the two forces are perpendicular.