A machine of efficiency 80% is used to lift a box. If the effort applied by the machine is twice the weight of the box. Calculate the velocity ratio of the machine? By: Sunday|Published on: May 19|Categories: Physics WAEC| 0 comments A. 0.50 B. 0.63 C. 0.80 D. 1.60 Correct Answer: Option B B. 0.63 Users Also Read These:A simple machine with an efficiency of 75% lifts a…A machine of velocity ratio 6 requires an effort of…A machine of velocity ratio 5 is used in lifting a…A machine whose efficiency is 60% has a velocity…A block and tackle pulley arrangement has 6 pulleys…SEE ALSO A radioactive element has a half life of 4 days. The fraction that has decayed in 16 days is?