<span>The maximum possible efficiency, i.e the efficiency of a Carnot engine , is give by the ratio of the absolute temperatures of hot and cold reservoir.
η_max = 1 - (T_c/T_h)
For this engine:
η_max = 1 - [ (20 +273)K/(600 + 273)K ] = 0.66 = 66%
The actual efficiency of the engine is 30%, i.e.
η = 0.3 ∙ 0.664 = 0.20 = 20 %
On the other hand thermal efficiency is defined as the ratio of work done to the amount of heat absorbed from hot reservoir:
η = W/Q_h
So the heat required from hot reservoir is:
Q_h = W/η = 1000J / 0.20 = 5000J</span>
Answer:
a) speed of the car = 22.22 m /s
b) ( i )
Explanation:
Negative work done by friction will be equal to reduction in kinetic energy of the car.
Frictional force = μ R = μ mg
work done by it = μ mg x 70 m.
Change in kinetic energy = 1/2 m v²
So , μ mg x 70 = 1/2 m v² ------------- ( 1 )
v = √2 x μ x 70 x g
= √2 x .36 x 70 x 9.8
22.22 m/s
As we have seen that m cancels out on both side of equation no ( 1 )
Answer:
compressions or refractions
Explanation:
Answer: Wind follows a pattern because the Earth is spinning in one motion. If we were spinning in one way then another we would have one day go by then the spinning cycle would change and we would have to go through that day all over again, it would not be logical because then we would be in the same season as well, we would be in one season for the rest of our lives until we died.
I don't know if this was helpfull or not but I hope it was somewhat close to helpful? If it is not then please do not report this, I am sorry if this was the least bit helpful.
HAVE A NICE DAY! :)
Evan could also grow some plants in the light? I don't have a clue but that would be my guess :) No points needed