Advertisements
Advertisements
प्रश्न
Using the equation `N = N_0e^(-lambdat)` obtain the relation between half-life (T) and decay constant (`lambda`) of a radioactive substance.
उत्तर
A relation between half-life (T) and decay constant(`lambda`) of a radioactive substance.
`N = N_o^(e^(-lambdat))`
when t = T
`N = N_o/2`
`:. N_o/2 = N_o^(e^(-lambdaT))`
`1/2 = e^(-lambdaT)`
`2/1 = e^(lambdaT)`
`Log_e 2 = lambdaT`
`T = (log_e 2)/lambda`
`T = 0.6931/lambda`
APPEARS IN
संबंधित प्रश्न
(a) Write the basic nuclear process involved in the emission of β+ in a symbolic form, by a radioactive nucleus.
(b) In the reactions given below:
(i)`""_16^11C->_y^zB+x+v`
(ii)`""_6^12C+_6^12C->_a^20 Ne + _b^c He`
Find the values of x, y, and z and a, b and c.
A radioactive nucleus 'A' undergoes a series of decays as given below:
The mass number and atomic number of A2 are 176 and 71 respectively. Determine the mass and atomic numbers of A4 and A.
A radioactive nucleus ‘A’ undergoes a series of decays according to the following scheme:
The mass number and atomic number of A are 180 and 72 respectively. What are these numbers for A4?
A freshly prepared radioactive source of half-life 2 h emits radiation of intensity which is 64 times the permissible safe level. The minimum time after which it would be possible to work safely with this source is
The isotope \[\ce{^57Co}\] decays by electron capture to \[\ce{^57Fe}\] with a half-life of 272 d. The \[\ce{^57Fe}\] nucleus is produced in an excited state, and it almost instantaneously emits gamma rays.
(a) Find the mean lifetime and decay constant for 57Co.
(b) If the activity of a radiation source 57Co is 2.0 µCi now, how many 57Co nuclei does the source contain?
c) What will be the activity after one year?
'Half-life' of a radioactive substance accounts for ______.
The half-life of a radioactive sample undergoing `alpha` - decay is 1.4 x 1017 s. If the number of nuclei in the sample is 2.0 x 1021, the activity of the sample is nearly ____________.
The half-life of a radioactive nuclide is 20 hrs. The fraction of the original activity that will remain after 40 hrs is ______.
The half-life of the radioactive substance is 40 days. The substance will disintegrate completely in
The half-life of `""_82^210Pb` is 22.3 y. How long will it take for its activity 0 30% of the initial activity?