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 %
Answer:
t = 2 seconds
Explanation:
In 2nd question, the question is given the attached figure.
Initial speed of the bus, u = 0
Acceleration of the bus, a = 8 m/s²
Final speed, v = 16 m/s
We need to find the time taken by the car to reach the stop. Acceleration of an object is given by :

t is time taken

The bus will take 2 seconds to reach the stop.
when object goes under acceleration
c).its velocity always increases
<h3><u>Additional</u><u> </u><u>information</u><u>:</u><u>-</u></h3>
★ Acceleration: Rate of increase in velocity.
★ Velocity: Distance travelled by a body per unit time in given direction is called velocity .