A wheel and an axle is used to raise a load whose weight is 800N when an effort of 250N is applied. If the radii of the wheel and axle are 800mm and 200mm respectively, the efficiency of the machine is by Sunday | Nov 7 | Physics JAMB | 0 comments A. 90% B. 80% C. 85% D. 87% Correct Answer: Option B – 80% Users Also Read These:What effort will a machine of efficiency 90% apply…A load of mass 120kg is raised vertically through a…A machine of velocity ratio 6 requires an effort of…A machine whose efficiency is 60% has a velocity…A wheel and axle of radii 800mm and 200mm…