<span>1.
</span><span>Efficiency is the
measure of how efficient a process is. It is used to assess the ability of a
process in avoiding waste energy, materials, money and time in doing a
desirable output. It is calculated as;
Efficiency = useful energy ouput / total energy input</span>
<span>.40 = useful work / 200</span>
<span>useful work = 80 joules</span>
<span>b. The coefficient of static friction for all contacting surfaces is μs=0.35. neglect friction at the rollers.
</span>
Answer:
(a) 1.257 x 10^5 J
(b) 1.456 Watt
Explanation:
Volume of blood, v = 7500 L = 7.5 m^3
Height, h = 1.63 m
density of blood, d = 1.05 x 10^3 kg/m^3
(a) work done = m x g x h
W = v x d x g x h = 7.5 x 1.05 x 1000 x 9.8 x 1.63 = 1.257 x 10^5 J
(b) time = 1 day = 24 x 60 x 60 s = 86400 seconds
Power = Work / time = 1.257 x 10^5 / 86400 = 1.456 Watt
The one fact that needs to be mentioned but isn't given anywhere on or around the graph is: The distance, on the vertical axis, is the distance FROM home. So any point on the graph where the distance is zero ... the point is in the x-axis ... is a point AT home.
Segment D ...
Walking AWAY from home; distance increases as time increases.
Segment B ...
Not walking; distance doesn't change as time increases.
Segment C ...
Walking away from home, but slower than before; distance increases as time increases, but not as fast. Slope is less than segment-D.
Segment A ...
Going home; distance is DEcreasing as time increases. Walking pretty fast ... the slope of the line is steep.