Mastering Physics: CP1 Summer 2015 HW 09 Google Chrome https:// mastering physic
ID: 1395647 • Letter: M
Question
Mastering Physics: CP1 Summer 2015 HW 09 Google Chrome https:// mastering physics.com /myct/itemView? assignment ProblemID- 49938888 ession CP1 Summer 2015 HW 09 Problem 13.61 Problem 13.61 Part B Air at 20°C flows through the tube shown in Figure 1). Assume that air is an ideal fluid. The density of air is 1.20 kg/ the density of What is the air speed v2 at point 2? mercury is 3600 kg/ms. Supp that di 3 Eam d d 1 Express your answer to two significant figures and include the appropriate units m Submit My Answers Give up Incorrect, Try Again, 3 attempts remaining Figure 1 Part C What is the volume flow rate? Express your answer using two significant figures Air 10 cm Submit My Answers Give up Incorrect, Try Again, 4 attempts remaining Hg Close Resources previous l 11 of 11 l return to assignment Continue Provide Feedback 6/21/20Explanation / Answer
d1 = 3 mm = 3*10^-3 m
d2 = 1 cm = 1*10^-2 m
area A1 = pi*d1^2/4 = (3.14*9*10^-6)/4 = 7.065*10^-6 m^2
A2 = pi*d2^2 /4 = (3.14*1*10^-4)/4 = 7.85*10^-5 m^2
ontinuity equation
A*v1 = A2*v2
v1 = A2*v2/A1 = (7.85*10^-5 /7.065*10^-6)*v1 = 11.111*v2 m/s
P2 = P1 + rhomercury*g*h
from bernoullis theorem
P1 + 0.5*rhoair*v1^2 = P2 + 0.5*rhoair*v2^2
P1 + 0.5*1.2*11.111^2*v2^2 = P1 + 13600*9.8*0.1 + 0.5*1.25*v2^2
74.0732*v2^2 = 13328 + 0.625*v2^2
v2 = 13.5 m/s <-------answer
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part(c)
volume flow rate = A2*v2
V = 7.85*10^-5*13.5
V = 105.975 m^3/s <-------answer