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3 years ago

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Calculate the efficiency for each machine, then answer the question. Machine A has an input work of 1,000 J and an output work o

f 250 J. Machine B has an input work of 500 J and an output work of 350 J. Machine C has an input work of 200 J and an output work of 150 J. Which machine is the most efficient?

2 answers:

Usimov [2.4K]3 years ago

7 0

Machine C. Machine A has an efficiency of 250/1000 = 0.25 = 25%, Machine B's efficiency is 350/500 = 0.7 = 70% and Machine C has an efficiency of 150/200 = 0.75 = 75%.

kati45 [8]3 years ago

7 0

Explanation:

Efficiency is defined as the measure of amount of work done by a system.

Mathematically, $Efficiency = \frac{Energy output}{Energy input} \times 100$

For machine A efficiency will be as follows.

Efficiency = $\frac{Energy output}{Energy input} \times 100$

= $\frac{250 J}{1,000 J} \times 100$

= 25%

For machine B efficiency will be as follows.

Efficiency = $\frac{Energy output}{Energy input} \times 100$

= $\frac{350 J}{500 J} \times 100$

= 70%

For machine C efficiency will be as follows.

Efficiency = $\frac{Energy output}{Energy input} \times 100$

= $\frac{150 J}{200 J} \times 100$

= 75%

Thus, we can see that efficiency is maximum in machine C, therefore, machine C is the most efficient.

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