Question

Easy Fluid Mechanics Question

Answer 1

Can someone please explain this question? I think it uses Bernoulli's equation:

Laboratories containing dangerous materials are often kept at a pressure slightly less than ambient pressure so that contaminants can be discharged through an exhaust system rather than leaked through cracks and around doors to other parts of the building. If the pressure in a laboratory is 0.1 inch of water below that of a hallway, with what velocity will air enter the room under the laboratory door? Assume viscous effects are negligible

Answer 2

yes, p2-p1 = (1/2) rho v^2.

convert 0.1 inch of water pressure drop to N/m^2 SI units
p2 - p1 = rhow g h =
(1000kg/m3)(9.8N/kg)(0.1inch)(1m/39.4inch) = 24.9N/m^2

use the density of air as rho in the equation with velocity:

v^2 = 2(24.9N/m^2)/(1.29 kg/m^3) = 38.6 (m/s )^2

v = 6.2 m/s

Answer 3

thanks. the weird monkey units throw me off :P