# Math Help - Calculus problem

1. ## Calculus problem

If a liquid has density $3$ and velocity field $v= -y{i}+x{j}+2z{k}$.
How do you find the rate of flow outward through the sphere $x^2+y^2+z^2=9$

2. perhaps a formula from her may help:
Volumetric flow rate - Wikipedia, the free encyclopedia