Question

used to raise an object of mass 30 kg. If the plane is 

inclined 5° above the horizontal and the coefficient of friction is 0.20, calculate the ideal 

mechanical advantage, actual mechanical advantage, and the efficiency of this machine.

Answer 1

Angle of inclination$(\theta)$ = $5\degree$

Ideal Mechanical Advantage = $cosec\theta$ = 11.47

Since, the coefficient of friction = 0.20

Actual Mechanical Advantage = $\dfrac{cosec\theta}{1+\mu}=\dfrac{11.47}{1.20}=9.56$

Efficiency of the machine = $\dfrac{9.56}{11.47}\times100=83.36\%$