What Determines the Repulsion Between Two Positively Charged Spheres?

Thread starter Ry122
Start date May 19, 2009
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Charges Force

AI Thread Summary

The discussion focuses on calculating the magnitude of the smaller charge between two positively charged spheres with a combined charge of 40C, separated by 50 cm, experiencing a repulsive force of 2.5 N. The user attempts to apply Coulomb's law but encounters issues with their calculations. They incorrectly apply the distance in the formula, neglecting to square it. The correct approach requires using the formula F = k(q1*q2)/r², ensuring the distance is squared. The user is advised to correct their calculations to find the smaller charge accurately.

May 19, 2009

Ry122

Each of two small non-conducting spheres is charged positively, the combined charge being 40C . When the two spheres are 50 cm apart, each sphere is repelled from the other by a force of magnitude 2.5 N. Determine the magnitude of the smaller of the two charges

my attempt:
use eq. F=kq1q2/d
2.5=((9x10^9)(40-q2)(q2))/.5
this gives me the wrong answer
what am i doing wrong?

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May 19, 2009

Pyrrhus

Homework Helper

You forgot r is square.

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