At time t= 0 , number of nuclei of a radioactive substance is 100. At t = 1 s this number becomes 90. Find the number of nuclei at t = 2s.

At time t= 0 , number of nuclei of a radioactive substance is 100. At

1.	At time t= 0 , number of nuclei of a radioactive substance is 100. At t = 1 s this number becomes 90. Find the number of nuclei at t = 2s.
Answer» SOLUTION :In 1 second 90% of the NUCLEI have remained undecayed, so in ANOTHER 1 second 90% of 90 i.e., 81 nuclei will REMAIN undecayed.

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At time t= 0 , number of nuclei of a radioactive substance is 100. At t = 1 s this number becomes 90. Find the number of nuclei at t = 2s.

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