# Solving for a variable within a definite integral using FindRoot

I want to solve for P in this equation:

Integrate[1/((P/(M*V)) - r*g - c*A*(V^2)*p/(2 M)), {V, 0, 26.82}] = s


, where all constants are given except P.

I've tried:

FindRoot [Integrate[1/((P/(M*V)) - r*g - c*A*(V^2)*p/(2 M)), {V, 0, 26.82}] == s, {P, 0}]


but I get this error:

FindRoot::nlnum: "The function value {Undefined} is not a list of numbers with dimensions {1} at {P} = {0.`}."

Any ideas on what I should try? I appreciate the help!

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Please post "all constants", The equation must be solved numerically –  belisarius Mar 5 at 7:17
Don't use P=0 as your starting value, since your function blows up there. –  Tom Dickens Mar 6 at 9:34