Question #1425d

1 Answer
Feb 2, 2018

F = k(Q_1Q_2)/r^2

Explanation:

Assuming the "look" is pertaining to the formula, the force acting on a charge Q_1 in the presence of another charge Q_2 is proportional to the the product of the charges Q_1*Q_2 and the distance separating them squared.

F ~~ (Q_1Q_2)/r^2

Hence,

F = k(Q_1Q_2)/r^2

k is the force (Columb's) constant: 9 xx 10^9 (Nm^2)/C^2

If you were Q_2 you would feel that Q_1 is tugging on you with invisible hands toward it provided it has an opposite charge than yours. Otherwise, you would feel being pushed away directly from Q_1. Now switch role, you are now Q_1...

So Coulomb's law also says that there are two forces, one acting on each charge body, have the same strength but in the opposite directions. (That's because of Newton's 3rd Law.) Can you see what the law look like now?

In the presence multiple charges, say 5 charges, what is the total force acting on any one of the charges then? Each charge sees the presence of 4 others, meaning there are 4 possible pairings that contribute to the forces. Each charge thus experiences 4 forces, tugging or pushing it.

Hope you can see and feel the force now.