Nuclei - Result Question 27

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28. The power obtained in a reactor using $U^{235}$ disintegration is $1000 kW$. The mass decay of $U^{235}$ per hour is

======= ####28. The power obtained in a reactor using $U^{235}$ disintegration is $1000 kW$. The mass decay of $U^{235}$ per hour is

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed:content/english/neet-pyq-chapterwise/physics/nuclei/nuclei—result-question-27.md (a) 10 microgram

(b) 20 microgram

(c) 40 microgram

(d) 1 microgram

[2011]

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Answer:

Correct Answer: 28. (c)

Solution:

(c) $E=mc^{2}$

$m=\frac{E}{c^{2}}$

So, mass decay per second $\frac{dm}{dt}=\frac{1}{c^{2}} \frac{dE}{dt}=\frac{1}{c^{2}}$ (Power in watt)

$=\frac{1}{(3 \times 10^{8})^{2}} \times 1000 \times 10^{3}$

and mass decay per hour $=\frac{dm}{dt} \times 60 \times 60$

$=\frac{1}{(3 \times 10^{8})^{2}} \times 10^{6} \times 3600=4 \times 10^{-8} kg$

$=40$ microgram