Moe ch.4, problem 4.1 What was exposure?

[Buchanan]

Please help me. I can not work out how to do this problem in Operational Health Physics Training by Moe.


4.1 Problem
A charged cylindrical ionization chamber having a diameter of 0.03 m and a length of 0.1m is drained of 1 ucoulomb as a result of exposure to an X-ray beam. What was the exposure?
Answer 0.011 c/kg


Thanks for any help.

[atomicarcheologist]

Hint: STP figures into the formulation, if I remember correctly.