The pressure difference, Δp, across a partial blockage in an artery (called a stenosis) is approximated by the equation Δp=KvμVD+Ku(A0A1−1)2rhoV2 where V is the blood velocity, μ the blood viscosity (FL−2T), rho the blood density (ML−3), D the artery diameter, A0 the area of the unobstructed artery, and A1 the area of the stenosis. Determine the dimensions of the constants Kv and Ku. Would this equation be valid in any system of units?

the velocity you are looking for is made up of two parts: horizontally velocity, vh, and its vertical velocity, vv. the actual velocity of the ball will be these two parts added together, and because velocity is a vector then they will need to be added vectorially.  

neglecting air resistance etc etc.,  

the horizontal velocity component will be constant (because there is no accelerating force in the horizontal direction.  

vh = 8 ms-1  

the vertical velocity component has an accelerating force: 'g'.  

using v = u +at where a = g = 9.81 ms-2.  

the vertical component of velocity, vv = 0 + gt = vv =9.81 x 2  

vv = 19.62 ms-1 . the zero appears because the virtical component of velocity at time t=0 is zero. remember, the ball was thrown horizontally.  

how fast it will be moving (it actual path (being a parabola )) will be the vector sum of these two.  

adding vectorally gives: -  

v = sqr root (8^2 + 19.62^2) = sqr root(64+384.9) = 21.18 or 21.2 ms-1

answeralert drivers who drift off the road;