In 1919, the 18th Amendment to the U.S. Constitution, which prohibited the sale and manufacture of alcohol, was ratified. It went into effect on January 16, 1920âbeginning the era known as Prohibition.
Because time constant calculations are important, and often needed, it is better to make the definition of the time constant (T) in a CR circuit: THE TIME TAKEN FOR THE VOLTAGE ACROSS A CAPACITOR TO INCREASE BY 63.2% OF THE DIFFERENCE BETWEEN ITS PRESENT AND FINAL VALUES.
The duration of on time is called the pulse width. To get varying analog values, you change, or modulate, that pulse width. If you repeat this on-off pattern fast enough with an LED for example, the result is as if the signal is a steady voltage between 0 and 5v controlling the brightness of the LED.In the graphic below, the green lines represent a regular time period.he duration of on time is called the pulse width. To get varying analog values, you change, or modulate, that pulse width. If you repeat this on-off pattern fast enough with an LED for example, the result is as if the signal is a steady voltage between 0 and 5v controlling the brightness of the LED.