A plane is traveling at a steady speed of 250 km/hr relative to the ground. An hour into the flight a passenger on the plane observes the plane pass Superman casually standing still in the sky talking on his cell phone. In a half hour the passenger then sees Superman passing by at a speed of 300 km/hr (also relative to the ground). a. Using Galilean relativity: according to the observer on the plane how fast is Superman moving relative to the plane?

b. Now find the answer to (a) using special relativity. How different is it?

c. Now the observer on the plane realizes that Superman is trying to stop a spaceship entering Earth's atmosphere. He sees Superman flying away from the Earth at a half speed of light (c) and the unknown object flying towards Earth at half the speed of light. From the perspective of the unknown object, how fast is Superman flying?

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.

When considering gravity acceleration and the force of acceleration, what must be true? a. the direction of acceleration must be perpendicular to the direction of the force. b. the direction of the force and the direction of acceleration must be the same as each other. c. the direction of the force and the direction of acceleration must be opposite of each other. d. the mass of the body must be the same as the acceleration of the body.

You are a sales representative for a company that makes a new alternate fuel for vehicles. you have prepared a presentation for the environmental engineers to sell your new product. what question do you expect the audience to ask regarding whether the new fuel will cause less damage to the environment? a. do we have to change any parts of the vehicle to use this alternate fuel? b. will the vehicles get better fuel mileage with the alternate fuel? c. how much greenhouse gas does your fuel produce compared with current fuel sources? d. is the alternate fuel more expensive than fossil fuel?