Recent content by hauthuong

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    How Does Initial Bullet Speed Relate to Conservation of Energy and Momentum?

    thank you A 1.72 kg object is suspended from a spring with k = 19.1 N/m. The mass is pulled 0.305 m downward from its equilibrium position and allowed to oscillate. What is the maximum kinentic energy of the object in J? 1/2 kx^2=1/2 mv^2 and I got it wrong too
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    How Does Initial Bullet Speed Relate to Conservation of Energy and Momentum?

    A bullet of mass 0.0021 kg is shot into a wooden block of mass 0.197 kg. They rise to a final height of 0.546 m as shown. What was the initial speed (in m/s) of the bullet before it hit the block? I figured out this one I got another one A 5.0 kg ball is attached to a vertical...
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    Calculating Energy Transformed by Friction in a Falling Satellite

    for kinetic energy I will us 1/2mv^2 .How do I find the V initial , Also, for Potential energy , I have to use GM1M2/r2 ? is it right? Thank you
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    Calculating Energy Transformed by Friction in a Falling Satellite

    A 500 kg satellite is in a orbit at an altitude of 500 km above the Earth's surface. because of the air friction, the satellite eventually falls to the Earth's surface, where it hits the ground with a speed of 2.00 km/s.how much energy was transformed into the internal energy by means of...
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    Conservative Force: Mechanical Energy, f(x) & x Value

    I am sorry for the typo fx and Fx is the same, for the second part : x=4 so the fx=0?
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    Conservative Force: Mechanical Energy, f(x) & x Value

    a single conservative force f(x) acts on a 1.0 kg particles that move along the x axis. the potential energy u(x) associated with f(x) is given by u(x)=-4xe^(-x/4) J, where x is in meters. at x=5.0 m, the particles has a kinetic energy of 2.0J. a) what is the mechanical energy of the system...
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    Block of wood friction problem

    thank for your reply . So the above problem does not give me enough info to solve. Is it right? (because it does not give me V and F)
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    Block of wood friction problem

    a 7 g bullet fires into a 1kg block of wood held in a vise, will penetrate the block a depth of 8.00 cm . this block of wood is placed on frictionless horizontal surface, and a 7.00 g bullet is fired from the gun into the block. to what depth will the bullet penetrate the block ? I bang my...
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    Rotating Wedge & Rise of Mass: Speed Calculation

    thank you, however, i do not quite understand why r=l. Could you please explain
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    Rotating Wedge & Rise of Mass: Speed Calculation

    the sloping side is frictionless, it is spun at constant speed by rotating the wedge. show that when a mass rises up the wedge a distance L, the speed of the mass is v=sqr(gLsin0) I got Fx=m(v^2/r) = mgsin0 v^2=g*sin0*r can I say r=L ? I got stuck, could you give me some hints thank you
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    Instaneous power delivered by the force at any timet

    Thank you very much, I got it, and I have another homework. A raindrop (m=3.35*10^-5 kg) falls vertically at a constant speed under the influence of gravity and air resistance. after the drop has fallen 100m, a)what is the work done by gravity? b)the energy discipated by air resistance? I...
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    How do u like Electrical Engineering

    Hello, I will be trained as integrated avionics systems in the U.S airforce . I am currently enroll in College. I lke to be computer programmer. when I search for jobs, most jobs are being offered if I have Electronic Engineer background. I frankly acknowledge I have no ideas what EE is. Could...
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    Instaneous power delivered by the force at any timet

    formula P=W/t or P=FV , and I don't know how to get t and and m involve in the formula
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    Instaneous power delivered by the force at any timet

    A force F acts on a particle of mass m. The particle starts from rest at t=0. a) show that the instaneous power delivered by the force at any timet is (F^2/m)*t Please give some directions how to solve it . Thank you
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