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Consider a star of mass m at a distance r form the center of a circular disk galaxy. Newton's law: F = GM(r)m/(r^2) where M(r) is the amount of mass inside the radius r. If we consider a uniform galaxy then density (p) is p = M/L where L is the length = 2*pi*r. So M(r) = p*2*pi*r. Setting the force of gravity equal to centripetal force (mv^2/r) you get G*2*pi*p = v^2 or
v = [2G*pi*p]^(1/2) which is a constant. Why do you need MOND theory. To me it seems Newtonian mechanics predicts a flat velocity curve.
v = [2G*pi*p]^(1/2) which is a constant. Why do you need MOND theory. To me it seems Newtonian mechanics predicts a flat velocity curve.