Recent content by lapo3399

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    Conservation of Energy by a Rolling Sphere

    Homework Statement A rolling ball traveling horizontally with a certain initial translational velocity comes to a hill with a defined height. Upon reaching the top, it flies off of a cliff and falls to the ground and ends up at the same relative height that it began at. If the final diagonal...
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    Finding Velocity as a Function of Time for a Particle with Retarding Force

    Oh. You integrate the left side with respect to v and the right with respect to t? So int[v^-1/2]dv=-kt/m + c 1/2v^1/2= -kt/m + c v=sqrt[-2kt/m+c] Would c somehow have to do with v0 then? Would it be v=sqrt[-2kt/m] + v0 ?
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    Finding Velocity as a Function of Time for a Particle with Retarding Force

    So you would integrate both sides with respect to t? If that is the case, I know that the right side will be -kt/m, but I do not understand how to perform the left side's integral.
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    Finding Velocity as a Function of Time for a Particle with Retarding Force

    Now that I think about it I think it should be done this way (though I'm not sure of this either because it ends with the square root of -kt/m... so unless k is negative it's not real): dv/dt = -(k/m)*sqrt(v) v = -(k/m)*int[sqrt(v)]dt v = -(k/m)*[t*sqrt(v)*(1/v)] v = -(k/m)*(t/v) v^2 = -kt/m v...
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    Finding Velocity as a Function of Time for a Particle with Retarding Force

    Homework Statement A retarding force acts on a particle with mass m and initial velocity v0 moving on a horizontal surface; this force is proportional to the square root of the instantaneous velocity of the particle: Fr = -k*sqrt(v) Find an expression for the velocity of the rock as a...
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    Kinetic/Potential Energy of Vehicle on Ramps

    Homework Statement Under the influence of gravity g, a vehicle with mass m and initial velocity v0, travels a distance d1 to the bottom of a frictionless ramp ("a" degrees above horizontal). It then begins to travel up a ramp ("b" degrees above horizontal) with friction coefficient u. What...
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    Solution to Simple Matrix Equation

    If a matrix squared is equal to the original matrix, does that mean that the original matrix had to be either the zero matrix or the identity matrix? Thanks.
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    Basic Solutions and Linear Combinations

    Just to clarify these concepts: if a homogeneous system of linear equations with four variables z1, z2, z3, and z4 yields a matrix in reduced row echelon form that defines (as an arbitrary example) the linear equations z1 = z3 + 0.5z4 = t + 0.5s z2 = 2z3 - z4 = 2t - s z3 = t z4 = s...
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    Is This Uncertainty Propagation Correct?

    Thanks! One more quick question - is the following uncertainty propagation correct also? \frac{1}{ \left( r \pm \Delta r \right)} = \frac{1}{r} \pm \frac{1}{ \Delta r} Thanks again.
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    Is This Uncertainty Propagation Correct?

    For the following calculation, would the uncertainty propagate as I have estimated? \frac{\left(a \pm \Delta a \right) + \left(b \pm \Delta b \right)}{\left(c \pm \Delta c \right) \cdot \left(d \pm \Delta d \right)} = \frac{a+b}{cd} \pm \frac{a+b}{cd} \left( \frac{\Delta a + \Delta b}{a +...
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    C/C++ Why is My C++ Program for the Bateman Equation Returning NAN?

    I've attempted that, and I finally realized what the problems where this morning. Firstly, the first for loop should read "i<(iter-1)", and I shouldn't have included the break statement in the other for loop.
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    Radioactive Decay chain and Masses of Products

    If anyone is experienced with C++ programming, could they please help here? I have another problem with this task: https://www.physicsforums.com/showthread.php?t=173810 Thanks!
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    C/C++ Why is My C++ Program for the Bateman Equation Returning NAN?

    Hello, I am attempting to create a program that will evaluate the Bateman equation for radiactive decay series, given several decay constants stored in a text file. I am not sure where this is going wrong, but no matter what chain member I enter in as the desired nuclide to find the mass...
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    Radioactive Decay chain and Masses of Products

    Thanks, I researched them and they are exactly what I need.
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