Physic Labs

Problem 2

A capacitor C charged to V₀ discharges through resistor R, with q(0)=CV₀. Find q(t) and discharge current i(t). Use the stated ideal model: quantities are constant or vary only as specified, with no extra drag, losses, or external influences. State a sign convention, keep units consistent, and use a classical approximation only where appropriate. (a) Set up the governing equation from a fundamental law. (b) Solve for the requested quantity under the stated conditions. (c) Check the result using a suitable limit, sign, or unit test, and report both the expression and its physical meaning.
Riout=q/C,iout=−dq/dtRi_{\rm out}=q/C,\quad i_{\rm out}=-dq/dt
problems.proof.analysis

Apply the fundamental law to the correct system and interval. A conservation law is valid only when the assumptions ensure its corresponding conservation condition.