Recent content by danielI

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    Setting up a differential equation

    So I need help with this diff eq. A train is placed in the tunnel AB and is will roll through it under its own weight, stop and return. Show that the time for a complete round trip is the same for all tunnels and calculate it. Using the fact that the force of gravity (inside the earth) is...
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    What Causes the String to Break in Different Physics Demonstrations?

    The reason I thought so was because the 200kg mass accelerates and so would the 150kg mass. While the 200*9,81 force in system 2 doesn't do that. Ofcourse there is some logical error with my reasoning. Also, here are all the videos...
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    What Causes the String to Break in Different Physics Demonstrations?

    Doc Al, My first theory regarding the picture was that 1 will accelerate but not system 2 since the 150kg cylinder is being pulled with a constan force. But this is wrong. I know how to calculate system 1. T - 150*9,81 = 150a 200*9,81 - T = 200a + => a = 1.401m/s^2 => T = 1681,65N...
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    What Causes the String to Break in Different Physics Demonstrations?

    At the end of this lesson. http://mfile.akamai.com/7870/rm/mitstorage.download.akamai.com/7870/8/8.01/f99/videolectures/wl99lec6-300k.rm Why does the lower string break, and then the upper and finally the lower one again? Has it anything to do with the speed he is pulling with? Look at the...
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    Calculate Force F at Point B for Slider along Guide

    How awfull isn't this? I've been working on this problem for hours now but my brain wasn't getting anywhere. While typing this message which was originally an explanation of my ideas I managed to come up with the solution. Basically at A we have the force mg while we at B have two forces mg and...
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    Calculate Force F at Point B for Slider along Guide

    If the slider along the smoth guide (i.e., no friction) on the horisontal plane has the speed 1.4m/s at A, what force F will the guide exert on the slider at point B? The weight of the slide is 0.12kg http://img522.imageshack.us/img522/750/slider4lo.png I'm able to calculate F at A = mg =...
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    How Deep Must a Steel Ball Sink in Oil to Reach Velocity v?

    Hey! In a test of resistance to motion in an oil bath, a small steel ball of mass m is released from rest at the surface. If the resistance to motion is given by R = kv where k is a constant, derive an expression for the depth h required for the ball to reach a velocity v. mg - kv = ma =...
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    Confirm this problem which involves friction

    Hello durt Okay, since the tilting part was wrong we keep the R_x and remove the R_y. Let the blue dot be origo. We will have two torques, the one by gravity and the one created by the force P. We start of with the one created by gravity. M_1 = mgd This will be counterclockwise. Then...
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    Confirm this problem which involves friction

    God day! The magnitude of force P is slowly increased. Does the homogeneous box of mass m slip or tip first? State the value of P which would cause each occurence. Neglect any effect of the size of the small feet. http://img75.imageshack.us/img75/629/friction5mb.png This is my work...
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    Calculating Tire/Tyre Forces in Weight Distribution of 1400kg Car

    Please? I'm not finding any other relationships.
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    Calculating Tire/Tyre Forces in Weight Distribution of 1400kg Car

    Now to a little harder problem. A 100kg weight is added on the red spot. Calculate the changes in the normal force reactions at the three wheels due to the weight of the box. http://img110.imageshack.us/img110/7644/car7pu.png In the last one I could use the equations d1/d2 = T2/T1 and...
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    Calculating Tire/Tyre Forces in Weight Distribution of 1400kg Car

    A car has 4 wheels?:biggrin: Cheers mate, cheers!:tongue:
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    Calculating Tire/Tyre Forces in Weight Distribution of 1400kg Car

    This is a lill awkward question but I need to know. A car has the mass 1400kg. What force will be distributed on each tire/tyre? ________________ / \ / \ ____/ \___ | |----d1--|G|-d2-| |...
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    Force and moment question on a sphear

    http://img457.imageshack.us/img457/7227/problem8sp.png If a ball is affected by a force P OR a moment M, what will this force or moment have to be in order to make the ball roll over the edge. My initial guess is that the force F\cos a has to equal (or be greater?) mg, where m is the mass...
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    Things that's accepted but has not been prooved yet

    Hi! I'm woundering what parts/things in physics that's being accepted but hasn't really been prooved yet. Is antineutrinos one of these things? Also if I remember this correctly neutrinos were accepted before they were prooved?
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