Exponential decay

A quantity is said to be subject to exponential decay if it decreases at a rate proportional to its value. Symbolically, this can be expressed as the following differential equation, where N is the quantity and λ is a positive number called the decay constant:

Related Topics:
Differential equation - Positive number

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:rac{dN}{dt} = -lambda N.

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The solution to this equation is

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:N = Ce^{-lambda t}. ,

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This is the form of the equation that is most commonly used to describe exponential decay. The constant of integration C is often written N_0 since it denotes the original quantity.

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