Key Equations
[ F = k \frac{{|q_1q_2|}}{{r^2}} ]
- (F) is the force between charges,
- (q_1) and (q_2) are the magnitudes of the charges,
- (r) is the distance between the centers of the two charges,
- (k) is Coulomb's constant ((8.987 \times 10^9 , \text{Nm}^2/\text{C}^2)).
Problem Solving Tips
- Always express charges in Coulombs and distances in meters to maintain consistency with the unit system.
- Remember that forces are vectors. When multiple charges are involved, vector addition may be needed to find the net force.
- Pay attention to the signs of the charges; like charges repel, and unlike charges attract.
Relevant Experiments
- Measuring the force between charged objects at varying distances gives empirical evidence supporting (F \propto 1/r^2).
- Using charge sensors and force meters, one can quantify the relationship between charge magnitude, distance, and force, confirming Coulomb's Law.
- Experiments using a torsion balance are classic methods to demonstrate Coulomb’s Law, similar to how Coulomb originally explored the law.