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Edemardil

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Everything posted by Edemardil

  1. Hi. So I have a rube goldberg I made in Algodoo and I have to finish a qualitative and quantitative description of it. I am getting an A in this class and I don't know why but there are two parts that I am having trouble with in my machine. If anyone can help. #1. The first is the collision on the top of the incline. I have to provide the equations and calculate the transfer of energy and momentum from the ball at the bottom of the ramp to the ball at the top. A ball drops into a hole, rolls horizontally for a few meters then rolls up an incline where it interacts with another ball at the top being held there by a lever. The ball going up the ramp pushed the smaller ball through the lever where it drops onto a ramp continuing the system. How would I calculate the momentum transferred between the ball that rolls up the incline ramp and the ball resting at the top? I know that the momentum is decreasing up the incline as well as the acceleration and velocity. But does the angle of the incline come into play? So far I've done: V'1 = (m1 – m2)/(m1 + m2)(v1) V'1 = (42.4kg - 12kg)/(42.4kg + 12kg)(4.30m/s) V'1 = 2.40 V'2 = 2m1 / (m1 + m2) (v1) V'2 = 2(42.4kg) / (42.4kg + 12kg) (4.30) V'2 = 6.70 But that's only really the velocity before and after the collision and it's probably wrong because I didn't know how to implement the incline when calculating those either. For energy transfer, I am going to use: 0.5m1v12 and for after the collision 0.5(m1+m2)v22 #2. This ball then drops down to interact with two vertical "levers" with axles in the middle of them. I'll post photos. I am really having trouble describing them more or less because I don't know what a good description of the objects them selves are. Are they levers? Latches? Hinges? Pendulums? This is keeping me from really describing them quantitatively because I am having trouble finding the right formulas for transferring energy, velocity, force all that, through that part.Could someone help me or vaguely lead me to a direction to look for both items? It is the yellow vertical poles that I am talking about. I have to provide equations about the change in type and amount of energy, and calculate the energy, velocity and force for the system. Which I guess ends with the last lever hitting the ball and the ball falling off the other side onto a "see-saw" but I'm thinking that maybe my system is too big or complicated and I should just do the part where the ball falls from the platform and lands on the see saw. But I will still need to describe the previous system of the small ball interacting with these two yellow levers or whatever.Link to images: https://imgur.com/a/WZ04zCR
  2. Hey everyone. I have built a Rube Goldberg in Algodoo and I have a section where a small ball is held on the top of a ramp by a lever with an axle. What happens is a larger ball interacts with them, pushing the smaller through the lever and it drops down continuing the machine. Would the only force acting on the small ball and the lever while it is at rest be friction basically?
  3. I figured out (a) but I am having trouble with (b):(a) What is the efficiency of an out of condition professor who 2.10e5 J of useful work while metabolizing 500 kcal of food energy?(b) How many food calories would a well-conditioned athlete metabolize in doing the same work with an efficiency of 25%?2. Relevant equationsOE + Wnc = OEfη = Work_out / Work_inWork_in = η * work_out3. The attempt at a solutionFor (a) I converted the calories to Joules1 kcal = 4184 J500 kcal (4184J/1 kcal) = 2.1e6 Jη = W_out/W_inη = (2.10e5J) / (2.10e6J)η = 10%(b) I assume I could input the 25% into the equation and work backwards but it's not giving me a correct anwser. I've tried the following:0.25 = (2.10e5J) / (kcal)kcal = (0.25)(2.10e5J)kcal = 52500JConvert the Joules to kcal and get something like 12kcalBut that's wrong also. Any guidance would be greatly appreciated. I wrote my equation wrong and got it now. Should be: 0.25 = (2.10e5) / (kcal) kcal = (210e5) / (I had times) (0.25) kcal = 840e3 J J to kcal 1kcal = 4184 J 840e3 / 4184 = 201 kcal
  4. That is extremely interesting. Thanks for that information. Where did you grow up, if I might ask?
  5. Interesting. She may have been making something up, but I remember it being a "Oh, wow that everyday thing is directly related to that?" It was like something that is passed down now in Americans or something along those lines. I'll keep looking.
  6. Hi everyone, I remember being in a chem lecture a few years back and the professor was talking about all of these common ailments and illnesses that people in the USA suffer from that have been linked to the radiation from testing and even the drops on Japan in WWII. Does anyone know anything about that or have a source for me? I am really interested in this and I'm doing some research.
  7. I'm new, how do I do that? I gave him a green arrow instead.
  8. Omg thank you. I have been going back to this problem for two DAYS and it was as simple as that. You my friend are my hero right now. Here is what I got final btw. ΔV = (1F)/(BA)*Vo 11.4e6(f) = a * Vo 11.4e6(f/a)=Vo ΔV/Vo = 6x10e-3 6x10e-3 = 1F/BA 6x10e-3 = F/(1.9e9 * A) 6e-2 * 190e3 = F/A 1.14e3 = F/A
  9. I am done with my homework this week but there is one question that I could not get anywhere with: A moonshiner makes the error of filling a glass jar to the brim and capping it tightly. The moonshine expands more than the glass when it warms up, in such a way that the volume increases by 0.6% (that is, ΔV/V0 = 6 ✕ 10-3) relative to the space available. Calculate the force exerted by the moonshine per square centimeter if the bulk modulus is 1.9 ✕ 109 N/m2, assuming the jar does not break. Answer __________ N/cm2 It later asks if the jar survives which I can figure out on my own but I do not even know where to start with this. I've read the weekly chapters twice now and spent maybe 2 hours on this and I'm just at the limit now. Could someone throw an equations at me or something? I don't want anyone to do it for me but like I said I have no idea even where to start with this. I know that F = m*a and to get pressure we can use P = F/A. So I have the pressure I guess as 1.9 ✕ 109 N/m2 and I guess I would have to convert that to N/cm^2 which would be 1.9e4 N/cm^2 So 1.9e4 N/cm^2 = F/A I'm just stuck and would be grateful if anyone could put any insight into this, if not for my homework, for my final at the end. I'm beginning to think this question is in the wrong section because the two chapters I read have nothing to do with this.
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