How To Find Half Life With Decay Rate

One-half-Life Calculator

The following tools can generate whatsoever 1 of the values from the other three in the one-half-life formula for a substance undergoing decay to decrease by half.

Half-Life Calculator

Delight provide any three of the post-obit to calculate the fourth value.

quantity remains N_t	initial quantity N₀	time t	one-half-life t_ane/ii

One-half-Life, Mean Lifetime, and Decay Abiding Conversion

Please provide whatsoever one of the following to get the other two.

half-life t_1/two		mean lifetime τ		decay constant λ
	=		=

Definition and Formula

Half-life is defined as the amount of time it takes a given quantity to decrease to half of its initial value. The term is about commonly used in relation to atoms undergoing radioactive decay, simply can be used to depict other types of disuse, whether exponential or not. One of the most well-known applications of one-half-life is carbon-14 dating. The half-life of carbon-xiv is approximately v,730 years, and it can be reliably used to measure out dates up to effectually l,000 years ago. The process of carbon-xiv dating was developed by William Libby, and is based on the fact that carbon-14 is constantly being made in the atmosphere. It is incorporated into plants through photosynthesis, and and then into animals when they consume plants. The carbon-14 undergoes radioactive decay once the plant or animate being dies, and measuring the amount of carbon-14 in a sample conveys information well-nigh when the found or animal died.

Below are shown three equivalent formulas describing exponential disuse:

North₀

N_t

t_ane/ii

If an archaeologist found a fossil sample that contained 25% carbon-fourteen in comparison to a living sample, the time of the fossil sample'due south death could be determined by rearranging equation i, since N_t , N₀ , and t_1/two are known.

This means that the fossil is 11,460 years quondam.

Derivation of the Human relationship Between Half-Life Constants

Using the above equations, it is also possible for a relationship to be derived between t_1/ii , τ, and λ. This relationship enables the conclusion of all values, as long as at to the lowest degree 1 is known.