Answer:
It's because it tips over the threshold from nucleate boiling, which we can see, to convection boiling, which we can't. ... Even if the steam stayed in the pot, it would still stop boiling when you removed the heat. The steam and water in a liquid/vapour mixture are at the same temperature (100ºC).
Explanation:
The efficiency of the steam engine is 78.9% because the rest of the work input is used to overcome friction.
<h3>What is efficiency of machines?</h3>
Efficiency of a machine expresses the useful work done by a a machine as a percentage.
- Efficiency of a machine = work output/work input × 100 %%
The efficiency of machines are always less than 100% percent due to energy losses due to friction and heat.
For the steam engine:
Work output = 225 J
Work input = 285 J
Efficiency = 225/285 × 100% = 78.9 %
Therefore, the efficiency of the steam engine is 78.9% because the rest of the work input is used to overcome friction.
Learn more about efficiency of machines at: brainly.com/question/7536036
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Answer:
write something like after the spacecraft launched all of the potential energy transformed into kinetic energy causing the spacecraft to go at an abnormal spped.
Explanation:
Answer:
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No; the sample could not be aluminum;
since the density of aluminum, " 2.7 g/cm³ " , is NOT close enough to the density of the sample, " 3.04 g/cm³ " .
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Explanation:
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Density is expressed as "mass per unit volume" ;
in which:
"mass, "m", is expressed in units of "g" (grams); and:
"Volume, "V", is expressed in units of "cm³ " (such as in this problem); or in units of "mL" ;
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{Note the exact conversion: " 1 cm³ = 1 mL " .}.
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The formula for density: D = m/V ;
Given: The density of aluminum is: 2.7 g/cm³.
Given: A sample has a mass of 52.0 g ; and Volume of 17.1 cm³ ; could it be aluminum?
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Let us divide the mass of the sample by the volume of the sample;
by using the formula:
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D = m / V ;
and see if the value is at, or very close to "2.7 g/cm³ ".
If it is, then it could be aluminum.
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The density for the sample:
D = (52.0 / 17.1) g/cm³ = 3.0409356725146199 g/cm³ ;
→round to "3 significant figures" ;
= 3.04 g/cm³ .
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No; the sample could not be aluminum; since the density of aluminum,
"2.7 g/cm³ " is NOT close enough to the density of the sample,
"3.04 g/cm³ " .
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