Question

The half life of a certain isotope is 1 day. What is the quantity of the isotopes after 2 day.
(a) one-half
(b) one-quarter
(c) one-eighth
(d) None of these

Answer 1

Answer:one quarter

Explanation: fraction after 1st half: 1/2

Fraction after 2nd half: 1/4

So according to that quantity of isotope is one quarter

Answer 2

Answer:

The quantity of isotope after 2 days is one-quarter

Explanation:

Let the initial quantity of isotope=1 unit

Given that,

Half life of isotope is 1 day

$t_{ \frac{1}{2} } = 1 \: day$

It means that,half of the quantity of isotopes decays in 1 day

Therefore,The quantity of isotope after 1 day is

$q_{1} = \frac{1}{2} \: units$

Now,the quantity of isotope after 2 days is

$q_{2} = \frac{ q_{1}}{2} = \frac{ \frac{1}{2} }{2} = \frac{1}{4} \: units$

Therefore,quantity of isotopes after 2 days is one-quarter

#SPJ2