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valkas [14]
3 years ago
14

A pulley system operates with 40% efficiency. if the work put in is 200 joules, how much useful work is produced?

Physics
2 answers:
QveST [7]3 years ago
8 0

<span>1.    </span><span>Efficiency is the measure of how efficient a process is. It is used to assess the ability of a process in avoiding waste energy, materials, money and time in doing a desirable output. It is calculated as;

Efficiency = useful energy ouput / total energy input</span>

<span>.40 = useful work / 200</span>

<span>useful work = 80 joules</span>

FinnZ [79.3K]3 years ago
5 0

Answer:

The useful work produced by a pulley system is 80 Joules.

Explanation:

Efficiency is a measure of how much work is preserved in a process. The formula for efficiency is the energy output, divided by the energy input, expressed as a percentage. A perfect process would have an efficiency of 100%.

η = efficiency (Greek letter "eta")

Wo = the work or energy produced by a process. Units are Joules (J).

Wi = the work or energy put in to a process. Units are Joules (J).

n = \frac{Wo}{Wi}

0.4 = \frac{Wo}{200J}

Wo = 0.4*200J

Wo = 80 J

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