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Half Life Calculator Radioactive Decay

Half-Life Equation:

\[ T_{1/2} = \frac{\ln(2)}{\lambda} \]

1/time

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1. What is Radioactive Half-Life?

The half-life of a radioactive isotope is the time required for half of the radioactive atoms present to decay. It's a fundamental concept in nuclear physics and chemistry that describes the rate of radioactive decay.

2. How Does the Calculator Work?

The calculator uses the half-life equation:

\[ T_{1/2} = \frac{\ln(2)}{\lambda} \]

Where:

Explanation: The equation shows that half-life is inversely proportional to the decay constant. A larger decay constant means faster decay and shorter half-life.

3. Importance of Half-Life Calculation

Details: Half-life calculations are essential in radiometric dating, nuclear medicine, radiation safety, and understanding nuclear reactions. They help determine how long radioactive materials remain hazardous or useful.

4. Using the Calculator

Tips: Enter the decay constant (λ) in reciprocal time units (e.g., 1/s, 1/year). The result will be in the same time units as your input (e.g., seconds if λ was in 1/s).

5. Frequently Asked Questions (FAQ)

Q1: What's the relationship between half-life and decay constant?
A: They are inversely related. Half-life = ln(2)/decay constant. A higher decay constant means shorter half-life.

Q2: Can I calculate decay constant from half-life?
A: Yes, simply rearrange the equation: λ = ln(2)/T1/2.

Q3: Why is ln(2) used in the equation?
A: It comes from solving the decay equation for when exactly half of the original quantity remains (N/N0 = 1/2).

Q4: What are typical units for decay constant?
A: Common units include 1/seconds (for fast decays) or 1/years (for slow decays). The units must be reciprocal time.

Q5: Does half-life depend on amount of material?
A: No, half-life is an intrinsic property of each radioactive isotope and doesn't depend on quantity.

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