Question

Which statement best explains the relationship between the electric force between two charged objects and the distance between them?

A.
As the distance increases by a factor, the electric force increases by the square of that factor.
B.
As the distance increases by a factor, the electric force increases by twice that factor.
C.
As the distance increases by a factor, the electric force decreases by twice that factor.
D.
As the distance increases by a factor, the electric force decreases by the same factor.
E.
As the distance increases by a factor, the electric force decreases by the square of that factor.

Answer 1

The electric force between two point charges is given by:

F = (1/(4πε₀))Qq/r²

F is the electric force, Q and q are the two charges, and r is the distance between the charges.

F is proportional to the inverse square of r. That means if you increase r by a factor k, then F will decrease by a factor k².

Choice E.