TIME CONSTANT 
Introduction  Questions  Quiz
INTRODUCTION 
In RC (resistive & capacitive) circuits, time constant is the time in seconds required to charge a capacitor to 63.2% of the applied voltage. This period is referred to as one time constant. After two time constants, the capacitor will be charged to 86.5% of the applied voltage. The same time constant applies for discharging a capacitor through a resistor. After one time constant, a capacitor will have discharged to (100  63.2) 36.8% of the initial stored charge.
t = time constant in seconds
.0001 * 470 000 = 47 seconds 
A001001001.... What is the meaning of the term "time constant" in an RL circuit?

A001001002.... What is the term for the time required for the capacitor in an RC circuit to be charged to 63.2% of the supply voltage?

A001001003.... What is the term for the time required for the current in an RL circuit to build up to 63.2% of the maximum value?

A001001004.... What is the term for the time it takes for a charged capacitor in an RC circuit to discharge to 36.8% of its initial value of stored charge?

A001001005.... What is meant by "back EMF" ?

A001001006.... After two time constants, the capacitor in an RC circuit is charged to what percentage of the supply voltage?

A001001007.... After two time constants, the capacitor in an RC circuit is discharged to what percentage of the starting voltage?

A001001008.... What is the time constant of a circuit having a 100 microfarad capacitor in series with a 470 kilohm resistor?

A001001009.... What is the time constant of a circuit having a 470 microfarad capacitor in series with a 470 kilohm resistor?

A001001010.... What is time constant of a circuit having a 220 microfarad capacitor in series with a 470 kilohm resistor?

QUIZ 
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