Question

Electrically neutral objects cannot exert an electrical force on each other, but they can exert a gravitational force on each other. electrically neutral objects cannot exert an electrical force on each other, but they can exert a gravitational force on each other.

a. True
b. False

Answer 1

The correct answer is
A) true

In fact, the electrical force can be present only if the two objects have a net charge different from zero, because the electrical force is proportional to the value of the charges:

`F_e = k_e (Q_1 Q_2)/(r^2)`
so, if they are neutral they cannot exert an electrical force between each other, because their charge Q is zero.

Viceversa, the gravitational force is always present when the objects have masses, since the force is proportional to the value of the masses:

`F_g = G (m_1 m_2)/(r^2)`
so, even if the two objetcs are neutral, if they have mass, they exert a gravitational force to each other.