I'm trying to plot a phase portrait for the equation:

(d^2/dt^2)y + b * (dy/dt)^2 = A, A > 0, b < 0

The first think I'm doing is just changing dy/dt = p[y], so the equation is:

p'[y] + b * (p[y])^2 = A, A > 0, b < 0

When i'm using StreamPlot and substitution for A and b, i see just blank graph. How is it better to implement it?

I'm trying to plot a phase portrait for the equation:

(d^2/dt^2)y + b * (dy/dt)^2 = A, A > 0, b < 0

The first thing I did was changing dy/dt to p[y], so the equation is:

p'[y] + b * (p[y])^2 = A, A > 0, b < 0

However, when I make a stream plot and substitute for A and b, I see a blank plot. How can I fix this?