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.
VC=q/C,VR=RioutV_C=q/C,\quad V_R=Ri_{\rm out}
problems.proof.analysis

Choose the physical system and sign convention specified in the problem, then identify the ideal assumptions. This fixes which forces, currents, or quantities can be exchanged during the process.