Recent content by yaser1989

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    Optimization of a Cylinder's Height and Radius

    I'm also having trouble with this problem. Given your recommendation, I added the area of the top and bottom to the surface area formula. The top and bottom are just circles so here's what I got: SA = 2*pi*r*h + 2*pi*r^2 If I solve for h and plug into the volume formula (pi*r^2*h), where do I...
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    Calculating Distance for Siren Sound Intensity Level

    Homework Statement Residents of Hawaii are warned of the approach of a tsunami by sirens mounted on the tops of towers. Suppose a siren produces a sound that has an intensity level of 120 dB at a distance of 2.0m. Homework Equations I = P / 4\pir^{2} The Attempt at a Solution I...
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    Cannon ball fired at castle - kinematics

    I got it. I rearranged Δx = Vit + 1/2at2 for time: t = Δx / Vi --> since acc'n in the x direction is 0, 1/2at2 = 0. So then, t = 500/ 100cosΘ where Θ = 20o = 5.321. Then I used y = (Vi )yt + 1/2at2 = (100sinΘ)(5.321) + 1/2(-9.81)(5.3212 )...
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    Can you confirm a simple Physics Velocity Question?

    The second one is right because both of the objects are moving in the same direction hence you would ADD the initial momentum of each mass.
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    Cannon ball fired at castle - kinematics

    Homework Statement A cannon fires a 10.0kg cannon ball 1.0m above the ground and at 20o to the horizontal with an initial speed of 100m/s. A castle 500m away has a wall 24.3m high. At what distance above the castle wall does the cannon ball pass? Homework Equations Δx = Vit + 1/2at2...
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