# GATE2015-2-12

If the fluid velocity for a potential flow is given by $V(x,y)=u(x,y)i+v(x,y)j$ with usual notations, then the slope of the potential line at $(x,y)$ is

1. $\dfrac{v}{u} \\$
2. $-\dfrac{u}{v} \\$
3. $\dfrac{u^2}{v^2} \\$
4. $\dfrac{u}{v}$

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