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.
Every self-regulated process has a time constant associated with it. The time constant is the amount of time it takes the process to change 63.2% of the final value of the process. In this example, the process changes by 10%. The time it takes to change 6.32 inches (63.2% of 10 inches), is the time constant. It takes five time constants in order for the process to complete the total change. The time constant is affected by the capacity of the process and the processâ resistance to change. The larger the process capacity, the longer the time constant, and the more resistive elements in the process (small pipes, penetrations, valves, etc), the longer the time constant.