Saturday

March 28, 2015

March 28, 2015

Posted by **Sandhya** on Friday, April 18, 2008 at 9:16pm.

2) What is the activity of a sample of 14C that contains 1.22E+21 nuclei?

- physics-Radioactivity -
**Damon**, Saturday, April 19, 2008 at 4:53pm1) n(t) = No e^-kt

where n is number at t and No is starting number

when t = 15. n/No = 1/17 = .0588

so

.0588 = e^-15k

ln .0588 = -15 k

k = -2.833/-15 = .18888

so

what is t when n/No = 1/2 ??

.5 = e^-.18888 t

ln .5 = -.693 = -.18888 t

t = 3.67 days half life

- physics-Radioactivity -
**Sandhya**, Saturday, April 19, 2008 at 10:58pmThanks a lot Damon

Is my answer for the second problem correct?

- physics-Radioactivity -

**Answer this Question**

**Related Questions**

phys - Although most natural potassium nuclei are stable 39K (93.3%) or 41K (6....

calc - The half-life of polonium is 139 days, but your sample will not be useful...

Physics ... - 116In nuclei are produced at the rate of 10 s-1. Calculate the ...

physics - Radioactive nuclei are produced in an irradiated sample at the rate of...

physics - 116In nuclei are produced at the rate of 10 s-1. Calculate the ...

physics - Although most natural potassium nuclei are stable 39K (93.3%) or 41K (...

science - 116In nuclei are produced at the rate of 10 s-1. Calculate the maximum...

physics - Suppose 32000 radioactive nuclei are in a sample. About how many ...

Chemistry - How many half lives will it take for a sample of a radioactive ...

math - An unknown radioactive element decays into non-radioactive substances. In...