CUET · PHYSICS · PYQ PAPER 2023
Which of the following is the correct equation for the law of radioactive decay?
(Symbols have their usual meaning.)
- A \( N(t) = N_0 e^{-t/\lambda} \)
- B \( N(t) = N_0 e^{-\lambda t} \)
- C \( N(t) = N_0 e^{-\lambda/t} \)
- D \( N(t) = N_0 e^{-2\lambda t} \)
Answer & Solution
Correct Answer
(B) \( N(t) = N_0 e^{-\lambda t} \)
Step-by-step Solution
Detailed explanation
The law of radioactive decay states that the number of nuclei decreases exponentially over time. The correct form is \(N(t)=N_0 e^{-\lambda t}\), where the decay constant ( \(\lambda\) ) and time ( \(t\) ) are multiplied in the exponent to represent this rate of change. B)…
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