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Radioactive Decay Constant Calculator

Radioactive Decay Constant Formula:

\[ \lambda = -\frac{\ln\left(\frac{\text{Remaining}}{\text{Initial}}\right)}{t} \]

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1. What is Radioactive Decay Constant?

The radioactive decay constant (λ) is a probability constant that represents the likelihood of a radioactive atom decaying per unit time. It is a fundamental parameter in nuclear physics that characterizes the rate of radioactive decay.

2. How Does the Calculator Work?

The calculator uses the decay constant formula:

\[ \lambda = -\frac{\ln\left(\frac{\text{Remaining}}{\text{Initial}}\right)}{t} \]

Where:

Explanation: The formula calculates the decay constant from the ratio of remaining to initial amount over a given time period.

3. Importance of Decay Constant Calculation

Details: The decay constant is crucial for determining half-life, predicting radioactive decay rates, dating archaeological samples, medical radiation therapy planning, and nuclear safety calculations.

4. Using the Calculator

Tips: Enter the remaining amount, initial amount, and time elapsed. All values must be positive, and remaining amount cannot exceed initial amount. Use consistent units for accurate results.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between decay constant and half-life?
A: Half-life (T½) = ln(2)/λ. The decay constant and half-life are inversely related - larger λ means shorter half-life.

Q2: What are typical units for decay constant?
A: Common units include per second (s⁻¹), per minute (min⁻¹), or per year (yr⁻¹), depending on the time unit used.

Q3: Can the decay constant be negative?
A: No, the decay constant is always positive as it represents a probability per unit time.

Q4: How accurate is this calculation?
A: The calculation is mathematically exact for exponential decay, which applies to most radioactive substances.

Q5: Does this work for all radioactive elements?
A: Yes, the formula applies to all substances that undergo exponential radioactive decay, which includes most radioactive materials.

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