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1. How do you calculate the energy required via torque when...

The "load" is just my way of saying the force. I understand the integral, I just wasn't sure if it was as easy as dropping in the FrSin[x] into the integral, but I guess it is. Thank you.
2. How do you calculate the energy required via torque when...

Let's say you have a lever arm connected to a load at the end. But the load is attached to a hinge, so no matter where the lever arm is, the load is always pointing down. I know that Energy = [integral] tau d_phi, but does that only work if the angle b/w arm and load is constant? What if the...
3. How does the Beer Lambert law work at non-normal incidences?

Okay, so I calculated Rp+Rs / 2, and I got 93% reflectivity, but that doesn't take into account the thickness of the film. I think it's more appropriate as a way to model a thick film where practically nothing makes it through the aluminum film. EDIT: Or is it just impossible, regardless of...
4. How does the Beer Lambert law work at non-normal incidences?

Thanks Dr Du. Since my light source is going to be unpolarized, the total reflectance is going to be (Rs+Rp)/2. Since both Rs and Rp are dependent on n2, would I just use the real index of refraction to calculate the amount reflected, and then when calculating what is attenuated, use the...
5. How does the Beer Lambert law work at non-normal incidences?

I want to calculate the intensity of a transmitted wave in a medium, but not at normal incidence. I want to consider the case of 45 degrees. What proportion of the intensity of the wave is lost by reflection? Specifically I am looking at a the reflection off of a thin film of aluminum...
6. Epicyclic motion and precession

Imagine I am standing but not moving forward/backward, but I am rotating my body about my own axis. Now imagine if I moved in a circular path as I was spinning on my own axis. Is this considered to be precessing (assuming the axis of rotations are always in the z direction)? My friend...
7. Acceleration and thrust of a rocket

I calculated velocity of the rocket by integrating the function for acceleration w.r.t time. Isn't that how thrust is defined? Yes, I am aware. In my original post, I specified that v was for gas ejection. Although I should have specified that the velocity in the graph is the velocity of...
8. Acceleration and thrust of a rocket

Hey guys, I want to know if I have an equation on thrust correct. I figured whats the acceleration as a function of time. You have the upward thrust = dm/dt v, assuming the mass flow rate and the gas ejection rate is constant and the downward force = -m(t) g, where m=m(t) since it's...
9. How does refrigeration work?

piVi / pfVf = nRTi / nRTf the n's and R's cancel out: piVi / pfVf = Ti / Tf now if the compressor can compress some special refrigerant gas to, lets say, Vf=\frac{1}{3}Vi and pf=2pi, then piVi / 2pi\frac{1}{3}Vi = Ti / Tf Then the pi's and Vi's cancel. Simplify to get...
10. How does refrigeration work?

unless i made a typo in my original post, I don't believe I have said anything erroneous. If you lower the volume, i.e. squeeze the gas into a smaller spot, the pressure increases. If you increase the volume, i.e. give the gas molecules more room to spread out, the pressure decreases...
11. How does refrigeration work?

Does this apply to every gas? When a gas expands, its pressure decreases. And like I said, is it possible for the increase in V to be equal to the decrease in p, resulting in no net change in T?
12. How does refrigeration work?

I know I can easily look this up on Wikipedia, but I chose to use my intuition on this one ;) Tell me if my intuition based approach is correct: You have a compressor which takes a refrigerant gas such as Freon and compresses/decompresses it. I'm imagining it works something like a piston in...