Question

Electricity problem (Coulomb's Law)

Answer 1

Two identical balls with no initial charge are connected with a string (k = 25 N/m) that is 1m long. Then the balls get charged with q and -q. The string now is 0.635m long. Which is the value of q?

Answer 2

"string" ?!?!

you mean spring ??!!??


use force or energy and Coulombs Law and Hooke's Law


using FORCE:

you have \(\large |F| = k_c \frac{q_1 \ q_2}{r^2} = k_c \frac{q^2}{r^2}\) from Coulomb

and

\(\large |F| = k_{spring} \ x\)

in equilibrium you are balancing the attractive force of the balls and the restorative force of the spring

Answer 3

That is simple, thanks a lot :)