Question 31.20: The isotope 7^16 N decays with a half-life of 7.4 s. a Calcu...

Cambridge International AS and A Level Physics Coursebook

The isotope $^{16} _{7}N$ decays with a half-life of 7.4 s.

a Calculate the decay constant for this nuclide.

b A sample of $^{16} _{7}N$ initially contains 5000 nuclei. Determine how many will remain after a time of:

i 14.8 s ii 20.0 s

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