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\mathrm{\eta}=1-\frac{\mathrm{w}}{\mathrm{n}\times\mathrm{E}}
FORMULA CHAPTER
Chapter 22 – Pythagoras Theorem
WBBSEClass 10Mathematics1 formulas
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Pulley Efficiency Including Pulley Weight
\mathrm{\eta}=1-\frac{\mathrm{w}}{\mathrm{n}\times\mathrm{E}}
SymbolMeaningUnit
ηEfficiency%
nVelocity ratio—
wWeight of pulleyN
EEffortN
Worked example
Given: n = 4, w = 20 N, E = 20 N Calculation: η = 1 − 20/(4 × 20) Answer: η = 0.75 or 75%