Created By : Rina Nayak

Reviewed By : Phani Ponnapalli

Last Updated : Apr 29, 2023

The Radioactive Decay Calculator is a free online application that displays an isotope's half-life.The online tool speeds up the process by displaying the isotope's radioactive decay in a fraction of a second.

Choose a Calculation
Initial Quantity(A0)
Half-life time (T1/2)
Decay Time(t)
Final activity(A)

What is meant by Radioactive Decay?

The spontaneous breakdown of the nucleus, which leads to the release of energy and matter from the atomic nucleus, is defined as radioactive decay in physics. It should be highlighted that radioisotopes lack sufficient binding energy to keep the nucleus in the atom, and it signifies that the radioisotopes' nuclei are unstable.

The atomic nucleus becomes unstable during radioactive decay, resulting in an imbalance in proton and neutron numbers.

Radioactive Decay Formula

This equation can be used to calculate the number of unstable nuclei that remain after time t. N(t) = N(0) * 0.5(t/T)

  • After time t has passed, N(t) is the quantity of a substance that remains
  • This substance's initial quantity is N(0)
  • The half-life is denoted by the letter T

A few more parameters can also be used to figure out how much of a chemical is left i.e. N(t) = N(0) * e(-t/τ) or N(t) = N(0) * e(-λt)

  • Where τ is the mean lifetime or the amount of time a nucleus stays intact on average.
  • λ is the rate of deterioration (rate of decay)

The following is a relationship between the three criteria that characterise a substance's radioactivity T = ln(2)/λ = ln(2)*τ

When a quantity diminishes at a pace proportional to the current quantity, it is called exponential decay. To put it mathematically we write dNdt=−λN

To solve the differential equation for N as a function of time, use the following formula N(t)=N(0)e−λt

N(t) is the quantity at time t, where N0 is the initial quantity and N(t) is the quantity at time t. The half-life is related to the rate of decay: t1/2=ln(2)/λ. The amount of material is given by n=N/NA, where NA is Avogadro's constant = 6.022 x 1023, and the activity is supplied by A=λN

FAQ’s on Radio Active Decay Calculator

1. What is the formula for calculating half-life?

To locate half-life, follow these steps: Divide ln 2 by the substance's decay constant.

2. Does the rate of deterioration change?

Yes, a radioactive material's decay half-life can be altered. When an unstable atomic nucleus spontaneously transitions to a lower-energy state and emits radiation, this is known as radioactive decay. This process transforms one atom into a different element or isotope.

3. How can you figure out how long it takes for something to decay?

When the amount of reduction is directly proportional to the amount that exists, this is known as exponential decay. Subtract the final count from the starting count. For example, if you started with 100 germs and ended up with 80 bacteria two hours later, divide 80 by 100 to get 0.8.

4. Is the temperature a factor in the decay constant?

The decay constant is solely determined by the radioactive nuclide and decay mechanism in question. It is independent of the quantity of nuclei present or any other environmental factors (such as temperature).