Recent content by bigguccisosa

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    Did I multiply this infinite series correctly?

    I haven't seen that identity before actually, but it does help to simplify things a bit. But how do you know what the mean square will be? With this formula I still see myself having to do a Cauchy product, which I think is where I am messing up with the indices.
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    Did I multiply this infinite series correctly?

    Homework Statement Hi, I have to find the RMS value of the inifnite series in the image below. Homework Equations https://en.wikipedia.org/wiki/Cauchy_product Allowed to assume that the time average of sin^2(wt) and cos^2(wt) = 1/2 The Attempt at a Solution So to get the RMS value I think I...
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    Lagrangian Mechanics - Kepler problem, Conservation

    Just wanted to update saying I have solved this so it doesn't stay unanswered, by applying the BAC - CAB rule and then replacing dp/dt with the force you find from the given potential.
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    Lagrangian Mechanics - Kepler problem, Conservation

    Homework Statement Attached. Homework Equations I am assuming the coordinate transformation is \vec{x}' = \vec{x} + \alpha\vec{\gamma} ? Then you have \vec{v}' = \vec{v} + \alpha\frac{d\vec{\gamma}}{dt} And r is the magnitude of the x vector. The Attempt at a Solution Part A. So to get the...
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    Particle moving inside an inverted cone - Lagrangian

    So in that case, should I have a Lagrangian with something like L = (unconstrained T-V) + (lagrange multiplier) (constraint)? I'm looking at https://en.wikipedia.org/wiki/Lagrange_multiplier#Example_1
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    Particle moving inside an inverted cone - Lagrangian

    Homework Statement Hi there! So I have a problem regarding a particle of mass m moving down an inverted cone under the force of gravity. The cone is linear with equation z(r) = r, in cylindrical coordinates (r, theta, z) A. Write down the Lagrangian, include the constraint that the particle...
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    Spring Pendulum - Lagrangian Mechanics

    Thanks I must have missed a (r_0 + r) factor in the first term when I was putting it into tex, I'll give it a shot with theta and theta dot as constants.
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    Spring Pendulum - Lagrangian Mechanics

    Homework Statement Please see attached image :) Homework Equations Euler-Lagrange Equation \frac{\partial{L}}{\partial{q}} - \frac{d}{dt}\frac{\partial{L}}{\partial{\dot{q}}} = 0 L = T - V The Attempt at a Solution a. The potential energy V is the potential energy from the spring and the...
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    Calculate Vertical Displacement with Drag Force Equation | Physics Homework

    You are looking for the distance required to reach a specific velocity, yes? If you know the time required and you have the function of the velocity, how would you then go from velocity to distance?
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    Calculate Vertical Displacement with Drag Force Equation | Physics Homework

    In your relevant equations you have the equation for velocity as it depends on time. Note that as t approaches infinity limit, v = -\frac{mg}{b} . This is terminal velocity. You want to find how far the distance must be to reach -\frac{x}{100}\frac{mg}{b} . Using this expression, you can solve...
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    Determining equilibrium position between two springs

    Equilibrium would imply that the net force on the mass is zero. The only 2 forces are the forces from either spring. So you must find the position at which the spring forces cancel out. Remember that force from a spring is F = -kx, where x is displacement from equilibrium position and is a...
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    How Do You Calculate the Final Image Position in a Three-Lens System?

    In your last calculation you used 35.33 instead of 35.53. If you use the correct value you obtained earlier, you get di = -317.94 instead. Now add the 2 lens distances (+104) and add the distance of the first object (+80), this gives you -133.94 cm. So you book just wants the distance relative...
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    Describe the angular momentum of the ball and net torque on

    Yes right hand in direction of velocity (and so linear momentum), curl towards r, so L points in positive k. For torque you should be looking at the direction of the Forces, and crossing them with r. Note that the tension points towards the centre, and the magnetic force points away (F =qv x B)...
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    Describe the angular momentum of the ball and net torque on

    Anways, what you have is a problem where you must determine what forces are acting on the particle, and how they influence the torque and angular momentum. Recall that \vec{\tau} = \vec{r} \times \vec{F} and \vec{L} = \vec{r} \times \vec{p} . The right hand rule will come in handy. There is...
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    Describe the angular momentum of the ball and net torque on

    Do the three stars indicate anything in particular (***)?
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