Home
Back
Decay Constant Formula:
| From: | To: |
The decay constant (λ) is a probability rate that describes how quickly a radioactive substance undergoes radioactive decay. It represents the fraction of atoms that decay per unit time and is inversely related to the half-life of the substance.
The calculator uses the decay constant formula:
Where:
Explanation: The formula shows that the decay constant is inversely proportional to the half-life. A shorter half-life corresponds to a larger decay constant, indicating faster radioactive decay.
Details: The decay constant is fundamental in nuclear physics, radiometric dating, medical imaging, and radiation therapy. It helps determine the rate of radioactive decay, which is crucial for safety assessments, dating archaeological artifacts, and calculating appropriate doses in nuclear medicine.
Tips: Enter the half-life in appropriate time units (seconds, minutes, hours, days, or years). The calculator will compute the decay constant in reciprocal time units. Ensure the half-life value is positive and non-zero.
Q1: What's the relationship between decay constant and half-life?
A: They are inversely related. The decay constant equals the natural logarithm of 2 divided by the half-life.
Q2: Can I use different time units?
A: Yes, but the decay constant will be in reciprocal units. For example, if you enter half-life in years, the decay constant will be per year.
Q3: What is the typical range of decay constants?
A: Decay constants vary widely depending on the isotope. Stable isotopes have λ = 0, while highly radioactive isotopes can have very large decay constants.
Q4: How is decay constant related to activity?
A: Radioactive activity (A) equals the decay constant (λ) multiplied by the number of radioactive atoms (N): A = λN.
Q5: Can this calculator be used for carbon dating?
A: Yes, if you know the half-life of carbon-14 (approximately 5730 years), you can calculate its decay constant.