Efficiency = Power Output / Power Input
Power Input = Rate of Energy input = 44.4 MJ/kg * 5 kg/h
= 222 MJ/h
But 1 hour = 3600seconds
222 MJ/h = 222 MJ/3600s = 0.061667 MW J/s = Watts
Power input = 0.061667 MW = 61 667 W
From Efficiency = Power Output / Power Input
28% = Power Output / 61667
Power Output = 0.28 * 61667
Power Output = 17266.76 W
Power Output = 17 267 W
Rate of heat Rejection = Power input - Power output
= 61667 - 17267 = 44400 W
Rate of heat Rejection = 44 400 W.
C- Copyright.
45mph is the answer if you do the math right
Here, ball is released... and it is in free fall means with zero initial velocity.
We know, s = ut + 1/2 at²
Here, s = 1000 m
u = 0
a = 10 m/s2
Substitute their values,
1000 = 0 + 1/2 * 10 * t²
2000 = 10 * t²
t² = 2000 /10
t = √200
t = 14.14 s
In short, Your Answer would be 14.14 seconds
Hope this helps!
Momentum is a product mass and velocity. If a certain object posses a kinetic energy, then it should have a momentum since it is moving which has a velocity. However, if the object is at rest and only has potential energy, then it would not have momentum. So, for the first question the answer would be yes, an object can have energy without having any momentum. For the second question, every object whether it is moving or at rest, possess some energy, potential for an object at rest and kinetic for an object that is moving. Thus, the answer would be no, an object having momentum would always have energy.
