Question 477: Atoms & Nuclei

Question

Two different radioactive elements with half lives '$$\mathrm{T}_1$$' and '$$\mathrm{T}_2$$' have undecayed atoms '$$\mathrm{N}_1$$' and '$$\mathrm{N}_2$$' respectively present at a given instant. The ratio of their activities at that instant is

Accepted Answer

$$	herefore \quad$$ Activity is given as:
$$\begin{aligned}
	herefore \quad \mathrm{A} & =\lambda \mathrm{N} \
\lambda & =\frac{\ln 2}{\mathrm{~T}}
\end{aligned}$$
$$	herefore \quad$$ Ratio of two different radioactive elements will be:
$$\begin{aligned}
& \frac{\mathrm{A}_1}{\mathrm{~A}_2}=\frac{\lambda_1 \mathrm{~N}_1}{\lambda_2 \mathrm{~N}_2} \
& \frac{\mathrm{A}_1}{\mathrm{~A}_2}=\frac{\frac{\ln 2}{\mathrm{~T}_1} \mathrm{~N}_1}{\frac{\ln 2}{\mathrm{~T}_2} \mathrm{~N}_2} \
& \frac{\mathrm{A}_1}{\mathrm{~A}_2}=\frac{\mathrm{N}_1 \mathrm{~T}_2}{\mathrm{~N}_2 \mathrm{~T}_1}
\end{aligned}$$

Answer

$$\frac{\mathrm{N}_1 \mathrm{~T}_1}{\mathrm{~N}_2 \mathrm{~T}_2}$$

Answer

$$\frac{\mathrm{N}_2 \mathrm{~T}_2}{\mathrm{~N}_1 \mathrm{~T}_1}$$

Answer

$$\frac{\mathrm{N}_1 \mathrm{~T}_2}{\mathrm{~N}_2 \mathrm{~T}_1}$$

Answer

$$\frac{\mathrm{N}_1 \mathrm{~N}_2}{\mathrm{~T}_1 \mathrm{~T}_2}$$

Atoms & Nuclei

Two different radioactive elements with half lives '$\mathrm{T}_1' and '\mathrm{T}_2' have undecayed atoms '\mathrm{N}_1' and '\mathrm{N}_2$' respectively present at a given instant. The ratio of their activities at that instant is

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