PURPOSE: To measure an RC time constant and to observe the shape of the charging and discharging curves.
DESCRIPTION: An RC circuit with meters is mounted on an overhead projector projectual. The voltage across the capacitor and the charging current are displayed. Either the voltage across the capacitor or the charging current (voltage across the series resistor) can also be displayed individually on the oscilloscope. Various combinations of resistance and capacitance can be plugged into the circuit. See circuit diagram below.
REFERENCES: (PIRA 5F30.15)
EQUIPMENT: RC circuit with meters on plastic sheet for overhead projector use, 30 and 100 microfarad capacitors, 5 and 10 kilohm resistors, overhead projector, oscilloscope on scope/TV cart.
SETUP TIME: 5 min.
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