Uma máquina térmica ideal opera recebe 450 J de uma fonte de calor e liberta 300J no ambiente. Uma segunda máquina térmica ideal opera recebendo 600J e libertando 450J. Se dividirmos o rendimento da segunda máquina pelo rendimento da primeira máquina, obteremos:

Yield of second machine / Yield of first machine = 0.75

Explanation:

Given:

Input of first machine = 450 J

Output  of first machine = 300 J

Input of second machine = 600 J

Output  of second machine = 450 J

Find:

Yield of second machine / Yield of first machine

Computation:

Yield of first machine = [Q1 - Q2] / Q1

Yield of first machine = [450 - 300] / 450

Yield of first machine = 1 / 3

Yield of second machine = [Q1 - Q2] / Q1

Yield of second machine = [600 - 450] / 600

Yield of second machine = 1 / 4

Yield of second machine / Yield of first machine = [1/4]/[1/3]

Yield of second machine / Yield of first machine = 3/4

Yield of second machine / Yield of first machine = 0.75

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