Higher Physics

Electricity and Electronics - Activity 15

Uses of capacitors - d.c. power supply

Aim - To show the effect of capacitors in the production of a smooth d.c. supply from an a.c.supply.     Instructions
The oscilloscope indicates the form of the output p.d. across the load resistor.
  • Select each of the circuits in turn.
  • Draw the circuits and sketch the traces produced.
  • Explain whether the trace produced in circuit 2 is a.c. or d.c.
  • Describe the effect of the capacitor on the trace produced in circuit 3.
  • State what effect the size of the capacitance has on the smoothing of the supply.
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