Recent content by physicskid72

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    My teacher marked me wrong but it think this is right

    Homework Statement A batter hits a fastball that is traveling at -38 m/s,. The ball has a mass of 0.145 kg. The change in momentum in the ball is 13.1 kg.m/s. what is the balls final momentum? B.) what is the final velocity of the baseball? Homework Equations deltaP = Pf - Pi P...
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    Equilateral triangle coulombs law problem

    okay I am slightly confused, why did you use 30 degrees instead of 60? and is my overall answer correct?
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    Equilateral triangle coulombs law problem

    i used 10^-9 and meters, and i see i made a mistake in the answer it should be 3.05 Newtons not micro coulombs.
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    Equilateral triangle coulombs law problem

    [Homework Statement 1.) Three charges are placed 25 cm apart in an equilateral triangle. Q1 has a charge of -6.0 nC, q2 has a charge of 4.0 nC and q3 has a charge of 4.0 nC. what is the force on q2? q1 is the top point, q2 is the bottom left leaving q3 on the bottom right Homework...
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    Dont understand this momentum problem

    it is still vague, do i combine the two equations? i mean if you simply rearrange you end up with two variables to solve for so you must have to use a combined formula right?
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    Dont understand this momentum problem

    i know the two equations are m1v1i +m2v2i = m1v1f + m2v2f and 1/2(m1)(v1i)^2 + 1/2(m2)(v2i)^2 = 1/2(m1)(v1f)^2 + 1/2(m2)(v2f)^2 or KEi = KEf I'm just not sure how to solve for the individual velocities.
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    Dont understand this momentum problem

    Homework Statement Two air track gliders of a mass 300 g and 200 g are moving towards each other in opposite directions with speeds of 50 cm/s and 100cm/s respectively. Take the direction of the more massive glider as positive. A.) determine the velocity of each glider after the...
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    Not enough information in this momentum question?

    Homework Statement Two air track gliders of a mass 300 g and 200 g are moving towards each other in opposite directions with speeds of 50 cm/s and 100cm/s respectively. Take the direction of the more massive glider as positive. A.) determine the velocity of each glider after the collision...
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    Conceptual momentum and work questions

    Homework Statement 1.) does a ball thrown upward lose momentum as it rises? explain. 2.)a duck walks along a long thin raft in the water. what does the raft try to do? what hinders this action? 3.)a golfball and a football have the same kinetic energy, which ball has the greatest...
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    A question regarding work with friction

    ok so i see i forgot to multiply the netforce by the distance so... f=ma = 25(0.55) = 13.75 W=Fd = (13.75)(35) = 481.25 J ok so the work done by the net force is 481.25 J - and that means that the because the object is now accelerating this external force must be doing...
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    A question regarding work with friction

    Homework Statement an object having a mass of 25 kg is moving at a steady speed on ice. The coefficient of friction is 0.12. a.) how much work is done moving the object 35 m? b.) how much work is done if the object is accelerated at 0.55 m/s/s over a distance of 35 m? Homework...
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    A question regarding power and hookes law

    Homework Statement A 2.8 m high spring has a spring constant of 12 N/m. How much power is required if the spring is compressed 1.2 m in 2.5s? Homework Equations Pe= 1/2kx^2 Power= W/t The Attempt at a Solution =1/2(12)(1.2)^2 =8.64 J so... Power = 8.64/2.5 = 3.456 watts...
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    Simple true and false questions

    Homework Statement true or false If there is no work there is no kinetic energy. There has to be a change in velocity for there to be a change in kinetic energy. when workiong with gravity, the difference in heights is important, the position above the Earth is not. the sum of...
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