Physic Labs

Problem 2

An ideal capacitor of capacitance C is charged to voltage V₀ and connected at t=0 to a resistor R initially carrying no current. Define discharge current as positive in the discharge direction and v(t) with the initial capacitor polarity; neglect inductance and wire resistance. (a) Establish the discharge differential equation and time constant τ. (b) Find v(t) and current i(t) for t≥0. (c) Calculate heat dissipated from 0 to t and check its limit as t approaches infinity. Use SI units throughout and treat components as ideal exactly as specified. State sign conventions when writing equations and retain units in final results.
v(t)=V0e−t/RCv(t)=V_0e^{-t/RC}
problems.proof.analysis

Substitute the established relation and isolate the requested quantity. Keep the physical solution consistent with the initial conditions and assumptions.