A solution containing active cobalt 2760Co having activity of 0.8μCi and decay constant λ is injected in an animal's body. If 1cm3 of blood is drawn from the animal's body after 10 hrs of injection, the activity found was 300 decays per minute. What is the volume of blood that is flowing in the body? (1Ci=3.7×1010 decay per second and at t=10hrse−λt=0.84)
A
6 litres
B
7 litres
C
4 litres
D
5 litres
Medium
JEE Mains
Open in App
Updated on : 2022-09-05
Solution
Verified by Toppr
Correct option is D)
The activity equation can be written as
−dtdN=λNoe−λt
given that
λNo=0.8μCi
Putting the values,
λNo=2.96×104
Let the volume of the blood flowing be V,
the activity would reduce by a factor of V10−3
Hence
VλNo10−3e−λt=300/60 (Both R.H.S. and L.H.S. are decay/s)