Recent content by Ike

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    Destructive Interference of a Sound Wave

    A sound wave with intensity 25 mW/m^2 interferes destructively with a sound wave with intensity 28 mW/m^2. What is the intensity of the superposition of the two? I've read through this section in my textbook three times now and I still have no clue as to how to go about figuring this out...
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    The Speed of a Block (Springs)

    Okay, I see what you mean now... So I need to find how far the spring is compressed by the block if it were at rest on the spring. Then I need to subtract the resultant energy loss from the total energy of the system. Thanks for your help!
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    The Speed of a Block (Springs)

    Well, I was assuming that at the moment just before the block hits the spring, the total energy is going to be kinetic. This is because the spring has not yet been compressed. Once the spring has been compressed as far as it will go (velocity = 0), all of the energy will be in spring...
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    Breaking Point for a Copper Wire

    Oh yes, and one Pascal is the same as one Newton per square meter. 1 Pa = 1 N/m^2
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    Breaking Point for a Copper Wire

    My main problem here is this... When a wire is stretched, it will return to it's original length if the weight is removed. This is true, unless the elastic limit has been reached, in which case the wire will be permanently stretched. Before this point, the proportional limit is met, in which...
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    The Speed of a Block (Springs)

    A 0.164-kg block is dropped straight downwards onto a vertical spring. The spring constant of the spring is 62 N/m. The block sticks to the spring and the spring compresses 0.17 m before coming to a momentary halt. What is the speed of the block just before it hits the spring? Give your...
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    Breaking Point for a Copper Wire

    What is the maximum load that could be suspended from a copper wire of length 1.9 m and radius 1.2 mm without breaking the wire? Copper has an elastic limit of 2.9 x 10^8 Pa and a tensile strength of 4.3 x 10^8 Pa. Give your answer in Newtons (N). Any thoughts? I'm completely lost.
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    Pressure Difference Across Airplane Wings

    I've been at this one for hours and can't get a handle on it... Can anyone give me a little help here? An airplane flies on a level flight path. There is a pressure difference of 545 Pa between the lower and upper surfaces of the wings. The area of each wing surface is about 138 m^2. The...
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