# R Demo -- introduction to variables
# resistance to air flow in the trachea

# https://phys.libretexts.org/Bookshelves/College_Physics/College_Physics_1e_(OpenStax)/12%3A_Fluid_Dynamics_and_Its_Biological_and_Medical_Applications/12.04%3A_Viscosity_and_Laminar_Flow_Poiseuilles_Law
# https://www.engineersedge.com/physics/viscosity_of_air_dynamic_and_kinematic_14483.htm
# https://pubmed.ncbi.nlm.nih.gov/6609569/
# https://pmc.ncbi.nlm.nih.gov/articles/PMC5900092/

eta = 1.81e-5
l=0.10
r= 0.0125
R=(8*eta*l)/(pi*r^4)

l=0.12
r= 0.0065
R=(8*eta*l)/(pi*r^4)