1. C

    Simple Mechanics problem - rotating the rod with a ball attached on a string

    To the end [A] of the rod [AB] with a length of d = 1.35 m a thin string with a length of l = 1.16 m was attached, at the other end of which a ping-pong ball is attached. The bar began to rotate in a horizontal plane with a constant angular velocity ω = 2.08 / s around the end B. Find the radius...
  2. M

    A Simple Example, and a Test

    Here is an example that I posted to a UseNet group that might be of interest to people on this forum: First, I wrote: The MCMIFM (the Momentarily Co-Moving Inertial Frame Montage) is the uniquely true and meaningful reference frame for the accelerating observer, because it is the ONLY...
  3. R

    Simple Harmonic Motion

    Please any help to solve this problem ? could any body help me to draw the shape of the movement ? or the free body diagram of the bead? Thanks in advance .
  4. L

    Simple Question - Preloading of a Cantilever Beam

    Hello, everyone. I have been trying to understand the meaning of the question from the posted image. I think that preloading has to do with adding bolts to the cantilever beam such that it can withstand the force from above, but I am not sure how exactly these bolts should be implemented...
  5. avito009

    Simple explanation.

    It is really simple putting 2 + 2 to get 4. The Danish astronomer, Olaus Roeme in 1676, first successfully measured the speed of light. So it was not einstein who measured the speed of light. So the logic is simple see when it was proved that gravity is a fictitious force by equating the two...
  6. avito009

    Simple explanation targeting layman.

    Einstein was right gravity is a fictitious force and hence obeys F=ma. The proof When we equate ma= GmM/r we get a= GM using this logic we can prove that gravitational acceleration does not depend on mass of the object and in order to do so we are equating the two equations so this proves...
  7. O

    Cheap / simple homemade projector

    I’m trying to build a relatively cheap and easy projector based on a Cree flashlight. I’ve experimented with cut outs, homemade slides, etc., and am pretty well convinced I’ll need to add a lease or two to make it viable. I’m hoping to project a relatively large image from say 30 feet away...
  8. O

    Mass flow rate of water in a hydraulic turbine

    Hello again. I have another problem that I'm working on: The intake to a hydraulic turbine installed in a dam is located at an elevation of 10 m above the turbine exit. Water enters at 20 C with negligible velocity and exits from the turbine at 10 m/s. The water passes through the turbine...
  9. O

    Energy being transferred to a container with air...

    Hello All. I would appreciate any help you can offer on this problem! Air is tightly contained in a closed, well-insulated tank with a volume of 0.5 m3. The tank is fitted with a paddle wheel that transfers energy to the air at a constant rate of 3 W for 1 hour. The initial density of the...
  10. Alan

    Susceptibility of a simple metal (Problem 31.6 in Ashcroft's

    1. The problem statement, all variables and given/known data The susceptibility of a simple metal has a contribution ##\chi_{c.c}## from the conduction electrons and a contribution ##\chi_{ion}## from the diamagnetic response of the closed-shell core electrons. Taking the conduction electron...
  11. F

    A simple thought experiment that gives a weird result

    Imagine a spaceship that moves with near-light speed regarding you. There are two balloons, one is in the head of the ship and the other is in the tail. In the middle of the ship there is a laser. It sends beams in both direction and those beams pop the balloons. For an observer on the ship...
  12. S

    Simple gas effusion question

    I can't seem to work out question 107. I can do 106 and 108. I keep getting B for 108 but the answer is A Can you see the link, if not here it is sorry
  13. A

    Simple question help needed please

    Firstly can I appologies for asking such a simple question, I last 'studied' physics thirty years ago at school and that was at a pre GCSE level and I was by no means a scholar. Would one get a stronger magnetic 'pull' from a magnet if the ferrous metal it was attracted to was larger in size...
  14. H

    Simple average speed problem

    This should be very easy, I have a feeling I'm missing soemthing obvious as the web form won't accept any of my answers. "A jet takes off from SFO (San Francisco, CA) and flies to ORD (Chicago, IL). The distance between the airports is 3000 km. After a 1-h layover, the jet returns to San...
  15. V

    Which is a simple yet accurate way to predict the type of flow in a rotating cylinder

    Hi, I am trying to find an empirical formula/graph/simple calculation that I can use to predict the flow pattern inside a horizontal rotating hollow cylinder. I intend*to find a method by which I can understand the onset of different flow patters (i.e. annular, rimming, pool .etc) by varying...
  16. J

    2 simple (I hope) questions about energy transformation

    I am trying to work out how to answer these 2 questions, and am a little lost. Any help will be most appreciated! ================================= Q1 ================================= During the rush hour, a moving staircase carries 120 commuters per minute up from an underground...
  17. S

    seems that mathtype doesn't parse a simple amsmath code

    I want to create something like this in MS Word by MathType 6.9 attachment 1 The code that I'm using is: \documentclass[a4paper]{book} \usepackage{geometry} \usepackage{amsmath} \begin{document} \begin{align} T_4 &= \langle \underline{k}\,.\,\underline{k}^{*^T}...
  18. Z

    pretty simple equation just blanking on the answer;

    so the equation I was left with was: 50cm = 2T -(.0625T^2) ....and I am to solve for T here the answer is: T=0 and 32, the latter being the answer I'm looking for but idk how we got there? and input would be valuable.
  19. J

    Simple explanation needed

    Hi everybody out there. I have a simple problem one which I in fact solved fairly easily with a few assumptions. However looking back on it I find that I do not fully understand one facet of the problem and I am asking if anyone can give me a simple explanation to clear my confusion. The...
  20. N

    Particle executing simple harmonic motion

    This refers to question 14. in the scan I attached. A particle executes simple harmonic motion with amplitude of 3.0 cm. At what displacement from the midpoint of its motion does its speed equal one half of its maximum speed? The answer to the problem is 2.6 cm. I don't know how to obtain this...