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According to the fundamental laws of electric charges, which statement is correct?

Charged objects have no effect on neutral objects.

Opposite charges repel each other.

Like charges repel each other, and opposite charges attract each other.

Like charges attract each other.

If the distance between two point charges is doubled, the electrostatic force between them will be:

Halved.

Doubled.

Four times greater.

One-fourth of the original force.

The value of Coulomb's constant (k) in SI units in a vacuum is approximately:

1.6 × 10⁻¹⁹C.

9 × 10⁻⁹N⋅m²/C².

9 × 10⁹ N⋅m²/C².

8.85 × 10⁻¹² F/m.

Which of the following pairs of forces are both non-contact forces?

Weight and upthrust.

Magnetic force and weight.

Air resistance force and electrostatic force.

Electrostatic force and friction force.

Which of the following affects the force between two charged bodies?

Distance between the bodies.

Weight of the bodies.

Mass of the bodies.

Speed of the bodies.