Recent content by rcummings89

This started out as a thought experiment and then I realized I was stuck in how to figure it out. If I have an airsoft rifle that uses compressed air in the tank at 3000 psi. It leaves the bottle regulated down to 800 psi. It then goes into a second regulator that reduces the pressure further...

If I have a tank of volume V, pressure P, and temperature T, what is the most effective way to determine the volume flow rate if I were to suddenly allow the air to discharge through a hose? My first thought was that I could use Boyle's Law to determine the compressed volume of air in the tank...

My understanding through most of college has been that friction occurs because of the surface roughness of two materials rubbing together; the smoother you make the surfaces, the less friction you have. Upon further research I can see that is not the entire case. Another problem for me is that...

Say I have a 0-10 lbf load cell that can measure the force it takes to lift an object. The load cell is accurate to 1% of the full scale. I take 5 measurements and get the following readings: 5.2, 5.1, 4.9, 5.0, & 4.8, all in lbf. Now I am asked to give the mean with the associated...

The problem asks for an approximation for the torque needed to rotate a disk that is separated from a stationary boundary by a viscous fluid, given that \tau = \mu \frac{U}{H}. I did it first using like this: T = F R F = \tau A = \mu \frac{U}{H} \pi R^2 where U = \Omega R And thus T = \mu...

pasmith, Thank you for clarifying, that definitely helps! But it does bring up another question for me though; again, I'm in the early stages of learning about this notation, and know that switching the indices changes εijk to εjik = -εijk, but why does it equal zero?

Homework Statement This is my first exposure to Einstein notation and I'm not sure if I'm understanding it entirely. Also I added this class after my instructor had already lectured about the topic and largely had to teach myself, so I ask for your patience in advance... The question is...

Homework Statement Please see the attached picture for the problem description. Now, I have a solution using the Lagrange method, (it should coincide with Newton's second law, I believe?) I just have a hard time getting my equations of motion to match. Homework Equations ∑Fext - M dv/dt =...

Hello, I just want to make sure I am understanding how to define degrees of freedom of an object. If you have a rolling ball moving strictly in the x-direction, it has two degrees of freedom: one from its rotation, and one from its translation? Or is it just one DoF because its translation...

Hello, the problem statement reads thus: "Consider a low-speed flow of air over an airplane wing at standard sea level conditions; the free-stream velocity far ahead of the wind [point 1] is 100 mi/h [44.7m/s]. The flow accelerates over the wing reaching a maximum velocity of 150 mi/h [67.1...

Thanks eigenperson, I had a feeling it was too easy lol. Ok, so much for that. Let me just ask you this then: if I want to see if a spoiler would increase the drag enough to cause a significant decrease in MPG, and I just want to know right away if it's even worth the effort (a...

Hello, I just want to make sure I am doing this right. As an example, if I want to add a spoiler or hood scoop to a car, after I find the correct coefficients of drag, can I assume that the total drag force acting on the car is ƩFD=drag of the car + drag of the spoiler+ drag of scoop, etc...

Someone showed me a graph that has to do with how a cylinder oscillates in uniform flow, starting from no oscillation, to high oscillation, back to none. I know the y-axis is amplitude/diameter and the x-axis is velocity / (natural frequency X diameter) I would just like to find out more...

Hello, I'm having trouble with a conduction problem, I have access to the answer but not the solution. I did it on my own and my value is half of what the answer is. Now, my calculus is a little rusty, but I don't know where I am going wrong. So the dimensions and temperatures of the sphere...

Ok, I think I was mixing up my concepts. Thanks a lot guys!