The radioactivity of a sample is R1 at a time T1 and R2 at a time T2. If the half life of the specimen is T, the number of atoms that have disintegrated in the time (T2−T1) is equal to:
A
(R1T1−R2T2)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
(R1−R2)
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
(R1−R2)/T
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
(R1−R2)T/0.693
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution
The correct option is D(R1−R2)T/0.693 The expression for the activity is A=λN=0.693×Nt1/2 R1=λ×N1=0.693×N1T......(1) R2=λ×N2=0.693×N2T......(2) From equations (1) and (2) R2−R1=0.693×N2T−0.693×N1T Hence, (R1−R2)T/0.693