An aerospace engineer is testing the backup power system of an atmospheric probe. The system relies on a capacitor bank discharging through an onboard heater. In five test runs, the engineer measures the time T1/2T_{1/2}T1/2 for the potential difference across the capacitor to drop to exactly half of its fully charged value.
The recorded values of T1/2T_{1/2}T1/2 are:
23.1 ms,22.6 ms,23.4 ms,22.8 ms,23.1 ms 23.1\text{ ms}, \quad 22.6\text{ ms}, \quad 23.4\text{ ms}, \quad 22.8\text{ ms}, \quad 23.1\text{ ms} 23.1 ms,22.6 ms,23.4 ms,22.8 ms,23.1 msDetermine the percentage uncertainty in the measurement of T1/2T_{1/2}T1/2.
Calculate the time constant τ\tauτ of the discharge circuit.
63 exam-style questions on AQA A Level Physics Capacitance (A-level only), covering Capacitance (A-level only), Parallel plate capacitor (A-level only), Energy stored by a capacitor (A-level only), and Capacitor charge and discharge (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.