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Varvara68 [4.7K]
3 years ago
5

A heat engine receives 7000 j of heat and loses 3000 j in each cycle. what is the efficiency of this engine?

Physics
1 answer:
Nonamiya [84]3 years ago
4 0

Answer: 57.1 %

Explanation:

The efficiency of the engine is given by:

\eta=\frac{Q_{used}}{Q_{in}}

where the numerator corresponds to the heat used by the engine, while the denominator corresponds to the heat in input to the engine.

In this problem, the heat in input is

Q_{in}=7000 J

while the heat used is

Q_{used}=7000 J-3000 J=4000 J

So, the efficiency is

\eta=\frac{4000 J}{7000 J}=0.571=57.1\%


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The question is in the picture
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Answer:

e) 120m/s

Explanation:

When the ball reaches its highest point, its velocity becomes zero, meaning

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where v_0 is the initial velocity.

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Now, after the ball has reached its highest point, it turns around and falls downwards. After time t_0 since it had reached the highest point, the ball has traveled downwards and the velocity v_f it has gained is

v_f = gt_0,

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which gives

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t_{tot} = t+t_0 = \dfrac{v_0}{g}+\dfrac{2v_0}{g}

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36= \dfrac{3v_0}{g},

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To develop muscle tone, a woman lifts a 2.50 kg weight held in her hand. She uses her biceps muscle to flex the lower arm throug
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To solve this problem we will use the concepts related to Torque as a function of the Force in proportion to the radius to which it is applied. In turn, we will use the concepts of energy expressed as Work, and which is described as the Torque's rate of change in proportion to angular displacement:

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r = Radius

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3 years ago
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Answer:

<h2>1.17 m/s²</h2>

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We have the final answer as

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