5. a charged object is able to repel a) only charged objects
b) neutral objects and neutral particles
c) neutral objects but not neutral particles
d) only neutral particles

A) only charged objects

Explanation:

The electrostatic force between two objects is given by

where

k is the Coulomb's constant

q1, q2 are the charges of the two objects

r is the separation between the two objects

We have:

- If the charges have same sign (q1 and q2 have same sign), the force is repulsive

- if the charges have opposite sign (q1 and q2 have opposite sign), the force is attractive

If one of the object is neutral, its charge is zero: q=0, so the electrostatic force is also zero.

So, the correct option is

A) only charged objects

because all the other options (B, C and D) involve the presence of neutral particles, for which q=0 and so the electrostatic force is also zero.

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