A high-intensity flash tube in a professional camera unit relies on a 4.5 μF4.5\ \mu\text{F}4.5 μF capacitor. When fully charged, the capacitor stores 90 mJ of energy. The capacitor then discharges through the flash tube, which behaves as a constant resistance of 25 Ω.
What is the maximum current during the discharge?
4.0 A4.0\text{ A}4.0 A
8.0 mA8.0\text{ mA}8.0 mA
8.0 A8.0\text{ A}8.0 A
5.7 A5.7\text{ A}5.7 A
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.