Coulomb’s law (16-1)

Question 1 of 4

Question

Absolute values of the point charges

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Question

Any two point charges $q_1$ and $q_2$ exert equally strong electric forces on each other.

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Review

If we replace $m$ and $G$ in Equation 10-2 with $q$ and $k$ , we see that Equation 16-1 is identical to Equation 10-2 for the gravitational force, but with an important difference: The electric force is attractive (like the gravitational force) if the two charges $q_1$ and $q_2$ have opposite signs (one negative and the other positive), but repulsive if $q_1$ and $q_2$ have the same sign (either both positive or both negative).