Efficiency = Power Output / Power Input
Power Input = Rate of Energy input = 44.4 MJ/kg * 5 kg/h
= 222 MJ/h
But 1 hour = 3600seconds
222 MJ/h = 222 MJ/3600s = 0.061667 MW J/s = Watts
Power input = 0.061667 MW = 61 667 W
From Efficiency = Power Output / Power Input
28% = Power Output / 61667
Power Output = 0.28 * 61667
Power Output = 17266.76 W
Power Output = 17 267 W
Rate of heat Rejection = Power input - Power output
= 61667 - 17267 = 44400 W
Rate of heat Rejection = 44 400 W.
C- Copyright.
Answer:
D) resistance, resistivity
Explanation:
Resistance is a physical quantity that indicates the opposition of an object to conduct electricity, this quantity depends on different factors such as temperature, material, object length, among other things. The resistance of two objects of the same material may be different, because it depends on the specifications of the object.
On the other hand, resistivity is a more general quantity, since it is assigned to materials and depends only on the nature of the material and its temperature.
So the resistivity is related to the meterial rather than the object.
The answer is: Resistance is a property of an object while resistivity is a property of a material.
<span>On the scale the only external forces are the man's weight acting downwards and the normal force which the scale exerts back to support his weight.
So F = Ma = mg + Fs
The normal force Fs (which is actually the reading on the scale) = Ma + Mg
But a = 0
So Fs = Mg which is just his weight.
Fs = 75 * 9.8 = 735N</span>
The answer is d that might help you
