Answer:
Equilibrium
Explanation:
An object is in equilibrium when the vector sum of the force acting on the object is equal to zero.
A body in equilibrium is at state of rest of rest or in motion with no external force acting on it.
- The resultant of all forces acting on the body is zero.
- In this case there is no net force and the body will be at rest.
Option number three is correct energy can be transformed and moved and released but it can't be destroyed and doesn't disappear.
Answer:
Explanation:
An equilibrium is a state in which opposing forces or influences are banned.
An example of equilibrium is in economics when supply and demand are equal. An example of equilibrium is when you are calm and steady. An example of equilibrium is when hot air and cold air are entering the room at the same time so that the overall temperature of the room does not change at all.
To develop this problem it is necessary to apply the concepts related to Gravitational Potential Energy.
Gravitational potential energy can be defined as

As M=m, then

Where,
m = Mass
G =Gravitational Universal Constant
R = Distance /Radius
PART A) As half its initial value is u'=2u, then



Therefore replacing we have that,

Re-arrange to find v,



Therefore the velocity when the separation has decreased to one-half its initial value is 816m/s
PART B) With a final separation distance of 2r, we have that

Therefore




Therefore the velocity when they are about to collide is 