A radioactive sample has an initial activity of 400 decays/s. Its activity 22 hours later is...

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A radioactive sample has an initial activity of 400 decays/s. Its activity 22 hours later is 25 decays/s. What is its half-life

Can you show how you do this. thank you

science physics

Answer 1

Answer #1

In each half life activity decreases to by 1/2 Ni= 400 , Nf = 25 Graphically 25 go !00 200 400 471/237 || 2+1/2 1/2 .. 4 half

Hope this helps...

Answer 2

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