Answer:
53.33 seconds
Explanation:
From the question;
- Power of the motor is 75 kW or 75000 W
- Depth or height is 150 m
- Volume of water is 400 m³
We are required to determine taken to raise the water from the given height.
We know that density of water is 1000 kg/m³
Therefore;
Mass of water = 400 m³ × 1000 kg/m³
= 4.0 × 10^5 kg
Thus, force required to raise the water;
= 4.0 × 10^5 kg × 10 N/kg
= 4.0 × 10^6 N
To determine the time;
we use the formula;
Time = work done ÷ power
= (4.0 × 10^6 N × 150 m) ÷ 75000 Joules/s
= 53.33 seconds
Therefore, time taken to raise the water is 53.33 seconds
