1. Bowling ball sitting in the rack:
kinetic energy = 0, because the ball is not in motion - we have only potential energy in this case
2. Bowling ball knocking pins down:
at the moment of knocking kinetic energy is increased, while the potential energy is decreased
Answer: a) 5 x 10^5 kg/s b) 444 MW
Explanation:
Kinetic energy per unit mass Ke is
Ke = V^2 / 2
Ke = 3^2 / 2 = 4.5 J/kg = 0.0045 kJ/kg
Now potential energy per unit mass Pe is
Pe = g x z = 9.8 x 90 = 882.9 J/kg = 0.8829 kJ/kg
The total mechanical energy of the River per unit mass e = Ke + Pe = 0.0045 + 0.8829 = 0.88744 J/kg
M = P x V = 1000 x 500 = 5 x 10^5 kg/s
b) power generation potential of the entire river at the location Wmax = Emech = M x Emech = 500,000 x 0.88744 = 444,000kW = 444MW
Do they give answer choices? or is it free write? i’ll help if you tell me!!
No if the volume of the object changes then density also changes but mass is constant
