Recent content by cmmcnamara

Homework Statement A rocket explodes into two fragments with the following information: Initial trajectory: 150 m/s in the x-direction, mass is 40kg Portion a, post explosion: 45 degree angle above the horizontal, 25kg Portion b, post explosion: 30 degree angle below the horizontal...

Anyone have some advice?

Homework Statement A refrigeration plant is rated at 1,200,000 Btu/hr with a cooling range of 10°F and a cold water temperature of 80°F. What is the maximum wet-bulb temperature allowable for 240 or 320 gpm? Homework Equations The Attempt at a Solution I am not really sure where...

Hahah, yea I just caught this about 30 seconds ago and was coming here to close up the thread. I normally go about everything symbolically but I've had my head up my arse with MathCAD this quarter learning to use it. Thanks so much for your response!

Hi all, ME major here that's very confused about the integrating op-amp. It's pretty simple what I am confused about, just unit problems. Suppose you have the following integrating op-amp circuit: Feedback capacitor: 10μF Input Resistance: 10kΩ Input Voltage: 5V[sin(100t)] My...

Roarks is an excellent book for formula look up but for a first timer (as it sounds you are) with beam bending, you may find it hard to follow. Pick up an older Strength of Materials book for cheap to really get the basics. Google Euler-Bernoulli beam theory as well.

Yea sorry about that. For local deflections used by Dunkerly I got: Left mass deflection=7.317E-4 in Right mass deflection=1.311E-3 in For total deflections used by Rayleigh I got: Left mass deflection=2.927E-3 in Right mass deflection=4.332E-3 in

The shaft has a 2" diameter so it should be pi/3

Hey SteamKing thanks for the quick reply. I attached a pdf of my work from MathCAD which also has a crudely drawn picture of the beam in question. The deflections that are given come from an Excel program that my professor gave us that will solve the beam deflections. For Dunkerly I found...

Hey guys, I was hoping someone could set me straight on the two main methods of calculating shaft critical speeds. I have a final coming up but I can't seem to get these two to agree. What I know: -Dunkerly underestimates, Rayleigh overestimates -Deflections used in Dunkerly are those...

Perhaps I need to reexamine this question after I take vibrations because I do keep seeing the idea of a natural frequency pop up which I am vaguely familiar with but it seems to be a different concept than the one I am dealing with currently. The ideas do seem to coincide somewhat though. Or...

When a gear transmits power it does so through a force which is NOT completely tangential to the gear circle. The portion which is tangential of this force is the transmitted load. The other portion of the force acts vertically downward and is equivalent to the transmitted load multiplied by the...

Right I understand why the critical speed is to be avoided. But I don't understand why forces acting on the shaft besides weight are not considered. The radial force on the shaft from the gear's radial load would contribute a force to deflection. I know tangential doesn't because that is seen by...

Hi all I'm a bit confused on shaft critical speed theories and I need some clarification. I'll just say what I know and point out if I am wrong in reasoning or something. I really appreciate the help. As I understand it, we are considered with the critical speed of the shaft because it is the...

Does anyone have any suggestions regarding this?