Recent content by lachy89

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    Estimating Car Speed from Skid Marks

    Speed is the magnitude of velocity and has no direction. EDIT: Assuming you are using the formula: v^2=u^2+2as you may need to check what you are using as v and u and be careful of your signs. 0 = u^2 +2as u^2=-2as Does that make sense?
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    Unknown Charge and Electric Field in a Right Triangle

    You have not posted any relevant equations. I think a good starting point would be looking for an equation for the electric field due to a point charge. As you have explained the electric field is in the -x direction. Would this mean that there is no y component at the point in question?
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    http://en.m.wikipedia.org/wiki/Darcy_friction_fzactor_formulae Look at the equation section ( I realize it is wikipedia but it should stillbe correct). As the 'f' is on both sides of the equation you may need to do some iterations or look for a simplified solution.
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    The Equation for te Darcy friction factor is a 'rough formula' u believe to be more accurate and incorporate your e values look up the Colebrook white equation, this might change your f value. Ylt should be in m, I am a little unsure on the formula you used for this. Isn't there a v^2 meant...
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    Sorry you are correct I'm not sure why I wrote that bit on velocity. I wrote it from my phone so Iay not have proof read too well, sorry. Yes the viscosity only depends on the temperature. Just check the magnitude though it may be *10^-6 or something like that.
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    No the whole portion flows in both. So in the smaller pipe the area goes down, but to make the Q constant, the velocity goes up. Exactly ^^. Once again Q stays constant, so if A goes down V must go up. Your units are correct. m^3/s = m/s * m^2 (if that makes sense) Seems like an...
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    My quoting skills are lacking so I apologise. The volumes per second are the same in each pipe. If 0.0025m^3 per second is going in the left end then 0.0025m^3 must be coming out the right end. If this was not the case there would either be a build up of fluid in the pipe system somewhere...
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    There is no loss of water in the transfer of water from pipe 1 to pipe 2. So the volume flowing through one pipe must equal the volume flowing in the other pipe. The larger pipe has a larger supply for a constant velocity, but the velocity is not constant the volumetric flow is. If you...
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    Yes, you need the area of figure b. This I'd the cross sectional area. Your 1st reply included the surface area of a cylinder not the area of the circle in figure b. I would suggest converting to metres in all hydraulic problems (except maybe some special cases I cannot think of an example)...
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    The area in the equation Q=A*V is referring to the 'cross-sectional area' and so just the area of the circle. This is pi*r^2 or pi*d^2/4 which is used more often at the uni I attend for circular cross-sectional area. Also be careful to convert the diameters to metres. Lastly looking...
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    How Do I Calculate Pressure Loss in Hydraulics with Two Pipes?

    Hello, I am just an undergraduate studying Civil Engineering/Physics so take this as 'guidance' not complete help if you wish. From Understanding Hydraulics, 2nd ed., Hamill The equations I find of relevance are: Q=V*A Flow is equal to Velocity x Area Re = V*D/(v) Re =...
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    Work to move charges from Infinity to origin

    Ok I think I have seen where I have made the mistake, thank you for your 'guidance' :)
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    Work to move charges from Infinity to origin

    Eight 3.0 μC charges are located at the corners of a "unit cube centered about the origin with 1mm edges" r= ((1*10^-3)^2+(1*10^-3)^2+(1*10^-3)^2))^(1/2)m =1.73*10^-3m Wouldn't that be the distance?
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    Work to move charges from Infinity to origin

    Homework Statement Eight 3.0 μC charges are located at the corners of a unit cube centered about the origin with 1mm edges. How much work does it take to bring a 5.0 μC charge from infinity to the origin? Homework Equations U= k*q1*q2/r The Attempt at a Solution r=...
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    Work to rotate a dipole in an electric field

    I'll show some of my working out in algebraic form so It will be easier to give some feedback. Torque = -p x E x sin(theta) Work = Torque x angle (in radians) Torque in this case is not constant as the torque changes with angle. Work = SUM OF ( Torque (theta) x d(theta)) from Pi/6 to...
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