- #1

adamworth

- 23

- 0

## Homework Statement

I have attached a picture of the question.

A 2 Ci

^{137}Cs source is equal to 2 x (3.7x10

^{10}Bq) = 7.4x10

^{10}s

^{-1}

8 hours a day, 5 days a week and for 50 weeks is a total duration in seconds of 7.2x10

^{6}s

An 8 cm lead shield = 0.08 m

IRR99 regulations set an effective dose limit as 20 millisieverts per year. Therefore, 10% of of their effective dose limit is 2 millisieverts = 0.02 m

^{2}s

^{-2}

## Homework Equations

None

## The Attempt at a Solution

[7.4x1010 s

^{-1}x 0.08 m]

**/**7.2x10

^{6}s = 0.02 m

^{2}s

^{-2}- d

d = 2.4x10

^{-5}m

I jiggle the equation about in different ways but keep getting small values for d.