Recent content by rasen58

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    B How to prevent static from building up on me

    I've recently been developing a lot of static electricity and it's very annoying as I get shocked when i touch metal objects or other people. This isn't like it happens every time I touch something though. It just happens after I take off my jacket for example. So then I have to find some metal...
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    How to express this statement using quantifiers

    There is a real number between any other two real numbers. I have two ways of writing it For all y and z there is some x such that y < x < z OR There is such an x such that for all y and z, y < x < z I'm confused as to which one is correct.
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    Kinetic friction on smooth then rough surface

    Thank you everyone! Just wanted to confirm.
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    Kinetic friction on smooth then rough surface

    Homework Statement Given a 2.0 kg mass at rest on a horizontal surface at point zero. For 30.0 m, a constant horizontal force of 6 N is applied to the mass. For the first 15 m, the surface is frictionless. For the second 15 m, there is friction between the surface and the mass. The 6 N force...
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    Interpolate value in velocity vs time table

    But if you're sketching it by hand, then you probably wouldn't know if it's exactly 27.1
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    Interpolate value in velocity vs time table

    Oh, I see now. So the velocity increased by 7 m/s over .5 s. So to find how much it increased every 0.1 s, I would do 7/5 = 1.4 m/s. To find the v at 3.8, that is .3 s past 3.5 so 23 + 3 * 1.4 = 27.2 m/s, which is pretty much the answer. Thanks!
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    Interpolate value in velocity vs time table

    Homework Statement Table gives the rectilinear motion of a 4kg mass over a 5 s time interval. When the time was 3.8 seconds, the velocity of the mass was approximately what Homework EquationsThe Attempt at a Solution I first just tried to find the average of the velocities at 3.5 and 4.0...
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    Water equivalent of calorimeter

    Can I cancel out the T's then? In that case, I would have c1m1 = c2m2 (0.2)(0.3) = (4.186)m2 m2 = 0.014 kg But the answer says it's 0.06 kg
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    Water equivalent of calorimeter

    Homework Statement The water equivalent in kg, of a calorimeter having a mass of 0.3 kg and a specific heat of 0.2 is Homework Equations q=cmT The Attempt at a Solution I wanted to set cmT = cmT for the water and calorimeter, but I don't know what the equilibrium temperature is. So what do I do?
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    Force required to change direction

    So v2-v1 is 50 m/s. But then what do I do. Finding the impulse by using (2 kg)(50m/s - 30m/s) doesn't give me the right answer.
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    Force required to change direction

    Homework Statement The speed of a 2 kg object changes from 30 m/s to 40 m/s during a 5 s time interval. During this same time interval, the velocity of the object changes in direction by 90 degrees. What average force was applied during the time interval? Homework Equations impulse = F.t The...
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    Dropping two balls, one with twice the mass

    Oh, wow, I was really stupid... The potential energies at the top aren't the same... because they have different masses. Wow, thanks. So the answer should be 2 and 4?
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    Dropping two balls, one with twice the mass

    Oh I see how they're related. So if I use 1 and 3 first, the potential energy should be equal to the kinetic energy at the bottom. So then, that means that they both have the same kinetic energy and since their masses differ, their velocities would have to differ. But I don't see why using the...
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