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Physics
Physics
Problem
The activity of a radioactive substance is
A
1
A_1
A
1
and
A
2
A_2
A
2
at time
t
1
t_1
t
1
and
t
2
t_2
t
2
respectively. If
t
2
>
t
1
t_2 > t_1
t
2
>
t
1
, then the ratio of
A
2
A
1
\frac{A_2}{A_1}
A
1
A
2
is: a.
e
−
λ
(
t
1
+
t
2
)
e^{-\lambda(t_1+t_2)}
e
−
λ
(
t
1
+
t
2
)
b.
e
λ
(
t
1
−
t
2
)
e^{\lambda(t_1-t_2)}
e
λ
(
t
1
−
t
2
)
c.
e
λ
(
t
2
−
t
1
)
e^{\lambda(t_2-t_1)}
e
λ
(
t
2
−
t
1
)
d.
e
t
2
/
t
1
e^{t_2/t_1}
e
t
2
/
t
1
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