Answer:
The answer is given below
Explanation:
Things provided in the statement:
Pressure <em>P1</em> = 120 kPa and <em>P2</em> = 5.6 MP or 5600 kPa
Power, <em>W</em> = 7 kW
Elevation difference = ∆z = 10 m
Mass of flow = m˙
So potential energy changes may be significant
Specific volume of water V= 0.001 m³/kg
Now putting the values in the formula
Power, <em>W </em>= m˙ x V (<em>P1 - P2</em>) + m˙ x g x ∆z
7 = m˙ x 0.001 (5600 - 120 ) + m˙ x 9.8 x 10 x (1 kJ/kg/ 1000 m^2/s^2)
7 = m˙ x 5.48 + m˙ x 0.098
7 = m ˙x 5.38
m˙ = 7/5.38
So mass flow m˙ = 1.301 kJ/s
Answer:
Removing some of the books reduced the mass of the box, and less force was needed to push it across the floor.
Law of conservation of momentum
67*x=4.2*5.6
That's a battery or other "power supply".
