Answer:
80%
Explanation:
Efficiency = Power output / Power input × 100 %
To calculate efficiency we need to find power output of electric pump.
We can use,
Work done = Energy change
Work done per second = Energy change per second
Work done per second = Power
Therefore, Power = Energy change per second
= Change in potential energy of water per second
=mgh / t
= 200× 10×6 / 10
= 1200 W = 1.2 kW
Now use the first equation to find efficiency,
Efficiency =
× 100%
= 80 %
Explanation:
a) Power = work / time = force × distance / time
P = Fd/t
P = (85 kg × 9.8 m/s²) (4.6 m) / (12 s)
P ≈ 319 W
b) P = Fd/t
0.70 (319 W) = (m × 9.8 m/s²) (4.6 m) / (9.6 s)
m = 47.6 kg
The Newton’s law that explains why the hands get red when you press them hard against a wall is Newton’s third law. When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite direction on the first body.
Answer:
During the segments B - C and D - E, the car stopped since the y axis is the distance and the distance stayed the same in between those segments.
For a simpler answer, the flat horizontal lines on the graph are the times when the car was stopped.