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Naddika [18.5K]
2 years ago
8

Find the radioactivity of a 1 g sample of 226Ra given that

a1" title="t_{1/2}=1620" alt="t_{1/2}=1620" align="absmiddle" class="latex-formula"> years and Avogadro's number = 6.023 × 10^{23}.
Physics
1 answer:
dangina [55]2 years ago
6 0

Answer:

Explanation:

No of atoms of Ra in 1 g of sample = 6.023 x 10²³ / 226

N = 2.66 x 10²¹

disintegration constant λ = .693 / half life

half life = 1620 x 365 x 60 x 60 x 24 = 5.1 x 10¹⁰ s

disintegration constant λ = .693 / 5.1 x 10¹⁰

radioactivity dn / dt = λN

= (.693 / 5.1 x 10¹⁰ )  x 2.66 x 10²¹

= .3614 x 10¹¹ per sec

= 3.614 x 10¹⁰ / s

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Hi there!

We can use the conservation of angular momentum to solve.

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Begin by converting rev/sec to rad sec:


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According to the above and the given information, we can write an equation and solve for ωf.

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2 years ago
Two skiers arrive at the bottom of a ramp travelling at the same speed. Friction may be ignored in this problem. One skier is an
inysia [295]

Answer:

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