- Question 1 (1 point)
A3.00E-6 kg snowflake is falling towards the ground with a constant velocity of <0.3, 0, -1.2> m/s. A sudden gust of wind lasting 2.0 s results in the snowflake moving with velocity < 2.3, 3.0,-2.2> m/s. What was the net force on the snowflake during the sudden gust of wind? (Assume the net force was constant during this period.)
A. < 3.0E-6,4.5E-6, -1.5E-6 > N
0
B. < 2.0, 3.0, -1.0 > N
0 <-6.0E-6, -9.0E-6, 3.0E-6 > N
O
C. < -1.0, -1.5, 0.5 > N
0
D. < 2.3E-6, 3.0 E-6, -2.2E-6 > N

Two horizontal plates with infinite length and width are separated by a distance h in the z direction. the bottom plate is moving at a velocity u. the incompressible fluid trapped between the plates is moving in the positive x-direction with the bottom plate. align gravity with positive z. assume that the flow is fully-developed and laminar. if the systems operates at steady state and the pressure gradient in x-direction can be ignored, do the following: 1. sketch your system 2. identify the coordinate system to be used. 3. show your coordinates and origin point on the sketch. list all your assumptions. 5. apply the continuity equation to your system. nts of navier stokes equations of choice to your system 7. solve the resulting differential equation to obtain the velocity profile within the system make sure to list your boundary conditions. check units of velocity 8. describe the velocity profile you obtain using engineering terminology. sketch that on the same sketch you provided in (1). 9. obtain the equation that describes the volumetric flow rate in the system. check the units.

An engine undergoes a cycle as shown in the diagram. during a complete cycle the work done by the gas is 28.5×103 j and the energy transferred thermally out is 99.4×103 j. there are 1.5×1024 gas molecules and they have three active degrees of freedom. 6. (6 pts) during which process(es) is energy transferred thermally into the gas? a. 1→2 b. 2→3 c. 4→1 d. 1→2 and 4→1 e. none of the above

Nitrogen (n2) undergoes an internally reversible process from 6 bar, 247°c during which pν1.2 = constant. the initial volume is 0.1 m3 and the work for the process is 121.14 kj. assuming ideal gas behavior, and neglecting kinetic and potential energy effects, determine heat transfer, in kj, and the entropy change, in kj/s. show the process on a t-s diagram.