Answer:
The force of gravity exerts a downward force. The floor exerts an upward force. Since these two forces are of equal magnitude and in opposite directions, they balance each other.
All of them have the same potential energy <span />
Answer:
- The distance between the charges is 5,335.026 m
Explanation:
To obtain the forces between the particles, we can use Coulomb's Law in scalar form, this is, the force between the particles will be:

where k is Coulomb's constant,
and
are the charges and d is the distance between the charges.
Working a little the equation, we can take:


And this equation will give us the distance between the charges. Taking the values of the problem

(the force has a minus sign, as its attractive)




And this is the distance between the charges.
Answer:
D. 1.8 × 102 newtons radially inward
Explanation:
The magnitude of the centripetal force is given by:

where
m is the mass of the object
v is the tangential speed
r is the radius of the circular trajector
In this problem, we have m = 4.0 kg, v = 6.0 m/s and r = 0.80 m, therefore substituting into the equation we get

The centripetal force is the force that keeps the object in a circular trajectory, so it is a force that is always directed inward (towards the centre of the circular path) and radially. Therefore, the correct answer is
D. 1.8 × 102 newtons radially inward