What you’ll learn3 learning objectivesChoose one objective for a focused lesson, or study the complete topic.19.3.1The variation with time of potential difference, charge and current• analyse graphs of the variation with time of potential difference, charge and current for a capacitor discharging through a resistorSyllabus objective19.3.2Τ = RC for the time constant for a capacitor discharging through a resistor• recall and use τ = RC for the time constant for a capacitor discharging through a resistorSyllabus objective19.3.3Equations of the form x = x0 e–(t / RC) where x could represent current• use equations of the form x = x0 e–(t / RC) where x could represent current, charge or potential difference for a capacitor discharging through a resistorSyllabus objective