problem about finding power in test about variances

Ok sorry Uwe.

Let me put a specific problem. I have some data for which sample size
n=15 and sample standard deviation s=0.008 mm. Now there are two parts of
the question. Here the random variable is diameter of rivet hole.
a) Is there a strong evidence to indicate that the standard deviation
of hole diameter exceeds 0.01 mm. Use aplha=0.05 .
 Now here Ho: variance = (0.01)^2 = 0.0001 mm
          H1: variance > 0.0001 mm
we can use test statistic  chisq = (n-1)*s^2 / 0.0001

Chisq has degree of freedom n-1=14. So using this test  statistic
we can check the null hypothesis. I can do this part. Now lets
look at the next part.

b)If true variance (sigma) is as large as 0.0125 mm, what sample size will
be required to detect this with power of at least 0.8 

Now this is the part where I am stuck and I want to use R to solve this
I know that R has power tests for other test statistics, but how do I solve this ?

Ati

problem about finding power in test about variances

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