[Three Physics Questions] 4. Why can electric force be either attractive or repulsive?
A. The values of the charges, q1 and q2, could be either positive or negative.
B. Coulomb’s constant K, does not have a negative sign.
C. The distance between the charges cannot be negative.
D. The force is calculated by the constant, not the charges.

5. Why is the equation for Newton’s law of Gravitation negative?
A. The negative sign indicates the force is made by mass.
B. The negative sign cancels out the negative sign of the gravitational constant.
C. The negative sign indicates the strength of force.
D. The negative sign indicates that the force is always attractive.

6. The force of gravity is stronger than the electrostatic force. True or false?