The Student Room Group

OCR physics The answer is C but how do I get there?

A student is modelling the decay of a radioactive source using the equation ΔN/Δt = −0.5N.The student decides to use Δt = 0.10s.The number N of radioactive nuclei is 2000 at t = 0.Part of the modelling spreadsheet from the student is shown below. t/s Number N of radioactive nuclei remaining at time t Number of nuclei decaying in the next 0.10s0.00 2000 1000.10 1900 0.200.30What is the value of N at t = 0.30s?A 1700B 1710C 1715D 1805
Use the equation N = N₀e^-λt , the way you have written out the question is quite confusing as I presume you just copied and pasted it, so the layout is a bit weird, but start off by using that equation.

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