direct current

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Electric current in which the electrons (negative charge) flow in one direction, and that does not reverse its flow as alternating current does. The electricity produced by a battery is direct current. Electromagnets and electric trains use direct current.

If in one second one coulomb of electrons passes a given point, then the current flow is 1 amp DC.

A cathode ray oscilloscope (CRO) is used to display the waveforms that show the pattern of how voltage and current vary over a period of time. The waveforms for DC are straight lines, as the voltage and current do not vary over a period of time. If a resistor is connected in a circuit and measurements of voltage across the resistor and current flowing through it are taken over a period of time, there will be no change in the voltage and current over this period. A plot of voltage or current against time produces a straight line.

The red disc, set towards the hoist, recalls the fight for independence. Green represents Islam, fertility, and the country's youth. Effective date: 25 January 1972. >>