Advertisements
Advertisements
प्रश्न
Half-lives of two radioactive elements A and B are 20 minutes and 40 minutes respectively. Initially, the samples have equal number of nuclei. Calculate the ratio of decayed numbers of A and B nuclei after 80 minutes.
उत्तर
(T1/2)A = 20 minutes
(T1/2)B = 40 minutes
t = 80 minutes
n = `"t"/("T"_(1/2))` N = `"N"_circ (1/2)^"n" = "t"/("T"_(1/2))`
For A : nA = `80/20 = 4`
`"N"_"A" = "N"_circ (1/2)^4 = "N"_circ/16`
Number of A Nucleided decayed =
`"N"_circ - "N"_circ/16 = (15"N"_circ)/16`
For B : nB = `80/40 = 2`
`"N"_"B" = "N"_circ (1/2)^2 = "N"_circ/4`
Number of A Nucleided decayed =
`"N"_circ - "N"_circ/4 = (3"N"_circ)/4`
`"N"_"A"/"N"_"B" = (15"N"_circ)/16 xx 4/(3 "N"_circ) = 5/4`
`"N"_"A"/"N"_"B" =` 5 : 4
APPEARS IN
संबंधित प्रश्न
Write two units of radioactivity. How are they interrelated?
It has been found that the Sun’s mass loss is 4.34 × 109 kg per second. How much energy per second would be radiated into space by the Sun?
Give the symbolic representation of alpha decay, beta decay and gamma emission.
In alpha decay, why the unstable nucleus emits \[\ce{^4_2He}\] nucleus? Why it does not emit four separate nucleons?
What is half-life of nucleus? Give the expression.
Discuss the gamma decay process with an example.
On your birthday, you measure the activity of the sample 210Bi which has a half-life of 5.01 days. The initial activity that you measure is 1µCi.
- What is the approximate activity of the sample on your next birthday? Calculate
- the decay constant
- the mean life
- initial number of atoms.
Characol pieces of tree is found from an archeological site. The carbon-14 content of this characol is only 17.5% that of equivalent sample of carbon from a living tree. What is the age of tree?
For a radioactive material, half-life is 10 minutes. If initially there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is:
The radio active decay of uranium into thorium is expressed by the 92U238 `->` 90Th234 + x where x is
