Half life formula
The number of unstable nuclei remaining after time t can be determined according to this equation:
N(t) = N(0) * 0.5^(t/T)
where:
N(t) is the remaining quantity of a substance after time t has elapsed.
N(0) is the initial quantity of this substance.
T is the half-life.
It is also possible to determine the remaining quantity of a substance using a few other parameters:
N(t) = N(0) * e^(-t/τ)
N(t) = N(0) * e^(-λt)
τ is the mean lifetime - the average amount of time a nucleus remains intact.
λ is the decay constant (rate of decay).
All three of the parameters characterizing a substance's radioactivity are related in the following way:
T = ln(2)/λ = ln(2)*τ
How to calculate the half life
Determine the initial amount of a substance. For example, N(0) = 2.5 kg.
Determine the final amount of a substance - for instance, N(t) = 2.1 kg.
Measure how long it took for that amount of material to decay. In our experiment, we observed that it took 5 minutes.
Input these values into our half life calculator. It will compute a result for you instantaneously - in this case, the half life is equal to 19.88 minutes.
If you are not certain that our calculator returned the correct result, you can always check it using the half life formula.
Answer:
pulmonary circulation
Explanation:
The pulmonary circulation moves the blood between the lungs and heart. Since the blood carries oxygen the heart pumps it to every body part including the lungs so we can maintain homeostasis.
Answer:
a vestigial structure
Explanation:
Vestigial structures are a rudimentary (or even functionless) version of a body part, but they have important functions in a closely correlated or evolutionarily close species, an example of which is the presence of eyes in fish of the genus Astyanax. The existence of these vestigial structures is strong evidence that evolution occurs in organisms, since this structure, today without much apparent function, may in the past have been extremely important to the ancestors of that species.
Fungi because of the rotting and in moist places