Answer:
The answer is the 1st one
energy never disappears, for example, if you give some kinetic energy to a ball and it stops few seconds later, friction steals this energy to ground which ball was going on. "Law of Conservation of Energy" tell us that energy can't disappear
Answer:
The height at which the object is moved is 10 meters.
Explanation:
Given that,
Force acting on the object, W = F = 490 N
The gravitational potential energy, P = 4900 J
We need to find the height at which the object is moved. We know that the gravitational potential energy is possessed due to its position. It is given by :
So, the height at which the object is moved is 10 meters. Hence, this is the required solution.
Answer: The work is 1863 N*m
Explanation:
We can define work as:
W = F*d
Where F is the force that the mover needs to apply to the refrigerator, and d is the distance that the refrigerator is moved.
To move the refrigerator, the minimal force that the mover needs to do is exactly the friction force (In this case, the refrigerator will move with constant speed).
Then we will have:
F = 230 N
and the distance is 8.1 meters, then the work will be:
W = 230N*8.1 m = 1863 N*m
Gear because each spike is a wedge shape that adds a mechanical advatage
