Complete question is;
Lamar writes several equations trying to better understand potential energy. What conclusion is best supported by Lamar’s work?
A) The elastic potential energy is the same for any distance from a reference point.
B) The gravitational potential energy equals the work needed to lift the object.
C) The gravitational potential energy is the same for any distance from a reference point.
D) The elastic potential energy equals the work needed to stretch the object
Answer:
B) The gravitational potential energy equals the work needed to lift the object.
Explanation:
In physics, we know that potential energy is the energy of a body at rest while the energy of a body in motion is known as kinetic energy.
However,the work required to lift a body from it's position of rest is equal to the Gravitational potential energy of that body.
Elastic potential energy is the one that is stored as a result of force applied to deform an elastic object. Thus, it is not equal to the work needed to stretch the object and it is also not the same for any distance from reference point.
Thus, looking at the options, Option B is correct
Answer:
The objects were 1.8m apart.
Explanation:
We will start stating the Coulomb's Law. It says that:

Where F_e is the electric force between the objects, q_1 and q_2 are the magnitude of the charge of the objects, r is the distance between them and K is the Coulomb's constant (
in vacuum). Solving for the distance r we have:

Plugging the given values into this equation, we obtain:

In words, the two charged objects were 1.8m apart.
If the velocity is constant then the acceleration of the object is zero.

Thus when we apply the equation

It remains

or equivalent