DieselShip's Online Content Library

Q2. A 73.5 μF capacitor is charged through a 6.8 kΩ resistor from a 24 V d.c. power supply.
(a) Calculate the instantaneous charging current at switch- on. (2)
(b) State the expression for the capacitor charging voltage and determine its value 1 second after switch -on. (4)
(c) Calculate the energy stored in the capacitor 1 seconds after switch-on. (2)
(d) After 1.5 seconds of charging the supply is switched off and the capacitor is discharged through a 22 kΩ resistor.
(i) Determine the time taken for the capacitor voltage to fall to 5 V. (4)
(ii) Sketch a clearly labelled graph with approximately scaled axes to show the capacitor voltage changes over its charge/discharge cycle. (4)