Question

Question 6 (5 Marks) The atmosphere from sea level to 11 km height is a constant lapse rate layer. Assuming a lapse rate of 0.0065°K/m. Calculate the temperature and pressure at a height of 7000 m, given sea level conditions of po=101325 N/m2 and To=15°C. Question 7 (5 Marks) A smooth plastic, 10-m-long garden hose with an inside diameter of 20 mm is used to drain a wading pool as is shown in Figure Q7. Calculate the flowrate from the pool using Bernoulli's equation, assuming frictional forces can be neglected. 0.2 m V 0.23 m Figure Q7 Question 8 (6 Marks) Use dimensional analysis to develop an equation for the velocity, C, of fluid flow in an open channel in terms of gravity, g, and the length, L, of the channel. Question 9 (5 Marks) The pressure drop experienced in a pipe, where flow is laminar, can be calculated using the Hagen-Poiseulle equation: 8μLV Apl What is the pressure drop experienced over a 1.8 m length of 8 mm diameter pipe with water (u=0.001 Pas) flowing which experiences a Reynolds number of 760?

Answer 1

A (7) 10 U-217 10.23 m appiy Bernoullis Bernoullis lauatim between free surface and Pipe exit 2 + V 2 + z - pg P2 9 f + 2₂ 2g Pi = P2 P2 = Patm atmospheric Pressum V TO Zz o ( Reference point) 200 + (0.23+0.2) 12 29 to T 29 2 - V 29 (0.43) V2 = 2.904 mis

8 (8) с қf (9) - ) -kgақ, 2. ke Piropastinad Constel k, (LT"] =( т°J [LT] =( 4 т?к, Compare Power of qnd T. k,+k, -1 -2 - - - (k) = Hence, - 2. Hena С= kg 12 1 1. c =KT 94

Q9) solution....

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