Section 1.9: Charge Conservation
This section explains the law of conservation of charge: the total charge in an isolated system remains constant. We also explore examples of charge transfer and redistribution.
Conservation of Charge:
\( \sum_i q_i^{\text{initial}} = \sum_i q_i^{\text{final}} \)
Charge can be transferred between objects but the total remains unchanged in an isolated system.
Example 1
Two spheres, initially neutral, touch a charged rod. Determine final charges after separation.
Use the principle of charge conservation and equal redistribution if spheres are identical:
\( q_{\text{final}} = \frac{q_{\text{rod}}}{2} \)
Practice Problems
- Two identical spheres with charges \(+6\mu C\) and \(-2\mu C\) touch. Find final charges after separation.
- Three conducting spheres in a line; charge redistribution after contact.
- Determine final charges when a charged rod touches two neutral spheres sequentially.
- A metal sphere receives electrons; find net charge change using conservation.
- Charges transfer in multiple touching spheres; compute final distribution.