Question

Stream and velocity potential functions for a 2-D flow field given by u = 2x and v = -2y are                    

(a) $\Psi$ = 2xy,  $\phi$ = x² – y²

(b) $\Psi$ = x²-y² ,  $\phi$ = 2xy

(c) $\Psi$ = x² y²;   $\phi$ = x² + y²

(d) $\Psi$ = x² + y²; $\phi$ = x²y²