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The activity of a source falls to 1/e of its starting… | StemPy Lab

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The activity of a source falls to 1/e of its starting value in 80 s. What is the decay constant?

PhysicsMediumHigh School (11–12)Modern Physics

Created by StemPy Lab

The activity of a source falls to $\dfrac{1}{e}$ of its starting value in $80$ s. What is the decay constant?

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← A sample of a radioactive element is heated from room temperature to a few hundred degrees. What happens to its half-life?Thorium-232 has an atomic mass of 232.038055 u. It decays by alpha emission into radium-228, which has an atomic mass of 228.031070 u. A helium-4 atom has 4.002603 u. Use 1 u = 931.494 MeV/c². How much energy is released in the decay? →

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