Recent content by bolivartech

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    How to Find Instantaneous Displacement in a Sinusoidal Wave?

    s = 3ms the answer is supposed to be -.433 μm
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    How to Find Instantaneous Displacement in a Sinusoidal Wave?

    Homework Statement A sinusoidal sound wave is described by the displacement wave function s(x,t)=(2.00 μm)cos⁡[(15.7 m^(-1) )x-(858 s^(-1) )t] b) Determine the instantaneous displacement from equilibrium of the elements of air at the position x = 0.050 m at t = 3.00 ms Homework...
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    Solve Balloon Height: Buoyancy & Weight Problem

    I haven't received a response but from what I can tell that is right. I did get the same answer as the prof, now I just have to find out if it was luck or if the process was correct. Thanks for the help!
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    Solve Balloon Height: Buoyancy & Weight Problem

    Ok so here is the thought process I am having. Find the change in force, use F=ma to find how much mass is lifted (string). Use that to determine how much in h is lifted. (mass total / height total = mass lifted / height lifted) So do I use the small difference in force between my normal...
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    Solve Balloon Height: Buoyancy & Weight Problem

    Homework Statement A helium filled balloon is tied to a 2.00-m-long, 0.050 0-kg uniform string. The balloon is spherical with a radius of 0.400 m. When released, it lifts a length h of string and then remains in equilibrium as shown in figure P14.51. Determine the value of h. The envelope of...
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    Angular Position, Velocity, and Accelration.

    Thanks, I don't know why I didn't see that... I stayed up way to late working on homework I actually enjoy doing. ω = dθ/dt = d/dt (5.00 + 10.0t + 2.00t2 ) = 10
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    Angular Position, Velocity, and Accelration.

    Homework Statement During a certain period of time, the angular position of a swinging door is described by θ = 5.00 + 10.0t + 2.00t2, where θ is in radians and t is in seconds. Determine the angular position, angular speed, and angular acceleration of the door (a) at t = 0 and (b) at t =...
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    Magnitude of acceleration with friction

    I've never seen it that way before but I think I'm starting to get it. In my free form diagram I drew the NL as mg + Fsin30. So Fk is not Ukmg, but UkNL. Which comes out to 11.82 in this scenario, and put in exactly as I had it setup before makes the acceleration 1.8. Thanks so much, not only...
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    Magnitude of acceleration with friction

    Alright I've thrown this in a few varying ways, but let me just say what I'm thinking so you can let me know where I've gone wrong. The frictional force is the coefficient * mass * gravity, and the Normal is mass*gravity. Since the force has a vertical element then it is also contributing to the...
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    Magnitude of acceleration with friction

    Homework Statement A block is pushed across a horizontal surface by the force shown (The force is from the left at an angle 30 degrees above the horizontal). If the coefficient of kinetic friction between the block and the surface is 0.30, F=20 N, theta=30 degrees, and M=3.0kg, what is the...
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    What is the Center of Mass of a Rod with Varying Linear Density?

    This is ridiculously when you put it that way. Thanks, I understand how to apply the formulas now. Hopefully when it gets rearranged for a test I will still see it.
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    What is the Center of Mass of a Rod with Varying Linear Density?

    Would I consider λ a constant. m = λ1/2x2 m = (50.0 g/m + (20.0)(.3m) g/m2)(1/2)(.32) of integrate it as well. Both ways that doesn't seem to be the right answer either. I get 2.43 if I integrate λ, and 2.52 if I don't.
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    What is the Center of Mass of a Rod with Varying Linear Density?

    Homework Statement A rod of length 30.0 cm has linear density (mass-per-length) given by λ = 50.0 g/m + 20.0x g/m2 where x is the distance from one end, measured in meters. (a) What is the mass of the rod? (b) How far from the x = 0 end is the center of mass? Homework...
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    What Is the Value of K in a Pendulum Lab?

    Homework Statement We did a pendulum lab and found Q then we were asked to find K from that. The professor gave us a formula K= 4pi2/m2 where m was the slope of a line on a graph of our periods vs lengthQ then stated it should be number we would recognize. I assumed maybe we were going to...
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    Time-Dependent Force: Solving for Speed & Displacement

    Homework Statement A time-dependent force, F = (8.00i – 4.00tj) N, where t is in seconds, is exerted on a 2.00-kg object initially at rest. (a) At what time will the object be moving with a speed of 15.0 m/s? (b) How far is the object from its initial position when its speed is 15.0 m/s...
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