Halfwit... No disrespect either. I always thought that the crux of Bernoulli's Law was that increased flow velocity lowered fluid pressure. I know applying this equation to the real world is more complicated because of things like viscosity and turbulence, but wouldn't the basic theory still hold true? I always found it funny how Bernoulli's Law seemed counterintuitive. But it is how we can explain why a fastball rises in baseball.
Yep, that's exactly why smaller syringes have a greater propensity for tissue damage. Having a greater pressure going into an even smaller area (needle) is what changes it from a high pressure to a high velocity fluid. Sure, viscosity takes into account the desire for the liquid to stick to the walls acting as a coefficient of friction, but given the huge pressure differential and small distance to travel given, I can't see it really changing too much.
None taken my brother.
Yes, but as the barrel of the syringe is what is generating the high pressure, and it has to flow through a smaller diameter area (needle), Bernoulli's states that the high pressure of the barrel translates to a high velocity in the smaller needle. (The needle itself will have a smaller pressure than the barrel) A fast ball actually rises because of the lower pressure being generated by higher velocity wind flowing on the top of the ball. It's the same principle of how a plane flies - as the top of the wing has a greater surface area, the velocity of the wind must be greater to reach the end of the wing at the same time as the wind from the bottom of the wing. This causes a lower pressure under the wing, generating lift.
