JAMB - Physics (2014 - No. 12)
A machine whose efficiency is 75% is used to lift a load of 1000N. Calculate the effort put in to the machine if it has a Velocity ratio of 4.
343.32N
233.33N
333.33N
334.33N
คำอธิบาย
\(\frac{MA}{VR}\times\frac{100}{1}=efficiency\)
\(\frac{L}{E}\frac{1}{VR}\times\frac{100}{1}=75\)
\(\frac{1000}{E}\frac{1}{4}\times\frac{100}{1}=75\)
\(E = \frac{250 \times 100}{75}\)
E = 333.3N
\(\frac{L}{E}\frac{1}{VR}\times\frac{100}{1}=75\)
\(\frac{1000}{E}\frac{1}{4}\times\frac{100}{1}=75\)
\(E = \frac{250 \times 100}{75}\)
E = 333.3N