Answer:
F = 1.6*10⁴ N
Explanation:
Given distance x = 0.15m, mass m = 1200kg, velocity v = 2m/s.
Unknown: force F
Force is given by Newton's law:
(1) 
The average force to stop an object from a velocity will be the same force necessary to accelerate an object from rest to the same velocity.
The distance for an object starting from rest for a constant acceleration is given by:
(2) 
The velocity for an object starting from rest for a constant acceleration:
(3) 
Using equation 2 and 3 to eliminate time t:
(4) 
Solving equation 4 for the acceleration a:
(5) 
Using equation1 to solve for the force F:
(6) 
Answer:
Liquid
Explanation:
To turn liquid into gas, you add heat, to remove heat from gas, you make liquid.
Answer:
220.7
Explanation:
distance traveled is 1.5*5=7.5m
PE gain is MGH=3*9.81*7.5=220.7
The answer is A. waterfall
To be considered as an engine , it should be a Man-made objects that could be used to produce power that creates motions.
From all the options above could be used to produce such power, but the waterfall is not made by mandkind