Question

write down the relation expressing the mechanical advantage of a lever for class 10

Answer 1

Let AF be the LOAD ARM and BF be the EFFORT ARM and Let the Load be L and Effort be E.

WORK DONE AT LOAD POINT=LOAD*LOAD ARM
=L*AF

WORK DONE AT EFFORT POINT=EFFORT*EFFORT ARM

=E*BF

ACCORDING TO THE PRINCIPLE OF MOMENTS,
Clockwise moment of load about the fulcrum= Anticlockwise moment of load about the fulcrum.

L*AF=E*BF

THEREFORE,
L/E=BF/AF
BUT, L/E=M.A.(i.e. Mechanical Advantage)
So,
M.A.=BF/AF
=EFFORT ARM/LOAD ARM.

Hope it helps.!!

Answer 2

Mechanical Advantage [ M.A]   =  Effort Arm / Load Arm.
                                                  =  Output force / Input Force.


Hope it helps......................