Two radio active elements X and Y have half lives of $50$ minutes and $100$ minutes respectively. Samples of X and Y initially contain equal number of atoms. After $200$ minutes, the ratio of number of atoms of X unchanged to that of Y is

4

No worries! We‘ve got your back. Try BYJU‘S free classes today!

2

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1 / 2

No worries! We‘ve got your back. Try BYJU‘S free classes today!

1 / 4

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct option is B $1 / 4$
X $\Rightarrow$ Initial amount of sample $= x$
Half life $=$ 50 min
After $200 m i n$ i.e., $4$ half lives, amount left unchanged $= (\frac{1}{2})^{4} = (\frac{1}{16})$
Y $\Rightarrow$ Initial amount of sample $= y$
Half life $=$ 100 min
After $200 m i n$ i.e., $2$ half lives, amount left or unchanged $= (\frac{1}{2})^{2} = \frac{1}{4}$
So, ratio of $\frac{X u n c h a n g e d}{Y u n c h a n g e d} = \frac{4}{16} = \frac{1}{4}$

Suggest Corrections

Similar questions

Q. Two radioactive elements

X

and

Y

have half lives of

50

and

100

minutes respectively. Initial sample of both the elements have same no. of atoms. The ratio of the remaining number of atoms of

X

and

Y

after

200

minutes is

Q. Half-lives of two radioactive elements A and B are 20 minutes and 40 minutes respectively. Initially the samples have equal number of nuclei. After 80 minutes, the ratio of decayed numbers of A and B nuclei will be

Half-lives of two radioactive elements A and B are 20 minutes and 40 minutes, respectively. Initially, the samples have equal number of nuclei. After 80 minutes, the ratio of decayed numbers of A and B nuciei will be:

Q. The half lives of radioactive elements

X

and

Y

are

3

minute and

27

minute respectively. If the activities of both are same, then the ratio of number of atoms of

X

and

Y

will be

Two radioactive isotopes P and Q have half-lives of 10 minutes and 15 minutes, respectively. Freshly prepared samples of each isotope initially contain the same number of atoms as one another, After 30 minutes, the ratio of $\frac{t h e n u m b e r o f a t o m s o f P}{t h e n u m b e r o f a t o m s o f Q}$ will be then:

Join BYJU'S Learning Program

Two radio active elements X and Y have half lives of 50 minutes and 100 minutes respectively. Samples of X and Y initially contain equal number of atoms. After 200 minutes, the ratio of number of atoms of X unchanged to that of Y is

Two radio active elements X and Y have half lives of $50$ minutes and $100$ minutes respectively. Samples of X and Y initially contain equal number of atoms. After $200$ minutes, the ratio of number of atoms of X unchanged to that of Y is