Try these:
http://www.google.com/search?client=safari&rls=en&q=t-test+power&ie=UTF-8&oe=UTF-8
Using a t test for dependent means based on .05 significance level, what is the power of each studies.
Study Effect size N Tails
(a) Small 20 one
(b) Medium 20 one
(c) medium 30 one
(d) medium 30 two
(e) large 30 two
1 answer