A pulley system has V.R. = 5 and M.A. = 4. Its efficiency is:
A5 percent
B120 percent
C100 percent
D80 percent
Answer & Solution
Correct answer: D. 80 percent
1. Efficiency = (M.A. / V.R.) * 100 percent.
2. = (4 / 5) * 100 percent.
3. = 80 percent.
4. So the system is 80 percent efficient.
_Source: Selina Concise Physics ICSE Class 10, Ch 3 'Machines' (aplustopper.com extract)_
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