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A wheel and axle is used to raise a load of 140N by a force of 20N applied to the brim of the wheel. If the
radii of the wheel and axle are 70cm and 5cm respectively, calculate the mechanical advantage, velocity
ratio and efficiency of the system.
M.A= load/effort =140N/20N= 7
V.R =radius of the wheel/radius of the axle= 70cm/5cm= 14
Efficiency= (M.A/V.R)*20
= (7/14)*20= 50%
Moraa orina answered the question on April 9, 2018 at 17:03
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