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

# A radioactive material decays by simultaneous emission of two particles with respective half-lives 1620 and 810 years. The time, in years, after which one-fourth of the material remains is:

A
1080
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
2430
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
3240
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
4860
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

## The correct option is A 1080−dNAdt=dNBdt=dNCdtλeqNA=λ1NA+λ2NAλeqNA=λ1NA+λ2NA λeq=λ1+λ2Since λα1t∴ Half life is related as.1(T1/2)effective=1(T1/2)A→B+1(T1/2)A→CEffective half life = 1620×8102430=540 yrs.⇒ It will 2 effective half lives for A to become 14th of its initial value.∴ Time = 1080 years.

Suggest Corrections
0
Join BYJU'S Learning Program
Related Videos
Sub-Atomic Particles
CHEMISTRY
Watch in App
Explore more
Join BYJU'S Learning Program