CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Two radioactive elements X and Y have half lives 6 min and 15 min respectively. An experiment starts with 8 times as many atoms of X as Y. How long it takes for the number of atoms of X left to equal the number of atoms of Y left?

A
6 min
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
12 min
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
48 min
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
30 min
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
E
24 min
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is D 30 min
t1/2 of X = 6 min
t1/2 of Y = 15 min
Given,
Xinitial:Yinitial=8:1
Let no. of half lives of X and Y be x and y for them to have equal amount.
Since time taken will be same.
6x=15y(1)
and
8(2)x=1(2)y(2)
From (2)
8=2xyxy=3(3).
From (1) & (3)
5y2y=3
y=2
x=5
Time taken = 2(15) =6(5) = 30 min.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Definition of Sets
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon