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TheFerruccio
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I'm computing an energy problem whereby a mass is being suspended from a pendulum. I think I have this right, but it would mean that I messed up with an earlier computation.
Two masses will impact, and they both hang on wires of 8.5 feet long. When both masses are hanging down, they are 1 inch apart. When I pull back one of the masses to impact the other, I need to exceed the 1 inch pullback, or the masses will not touch on the upswing. I need to compute the speed of the impact.
So, I pulled back the mass 3 inches, and it will swing through the 2 inch wide "dead zone" and then impact after exceeding 1 inch distance in the other direction. What is the velocity? I said that there is a transfer of potential energy to kinetic energy, and I used pythagorean's theorem to figure out the difference in heights.
Length of string (and hypotenuse) = always 8.5 feet.
Horizontal pullback distance = 7 inches
Energy difference = pullback at 7 inches - pullback at 1 inch
Thus, [itex]v = \sqrt_{\left(\sqrt_{8.5^2-(1/12)^2} - \sqrt_{8.5^2-(7/12)^2}\right)2g}[/itex]
This gets me a velocity of approximately 1.12 feet per second. Is this right? Also, for some reason, the tex integration isn't working for me anymore. It just draws a box around what I wrote. I checked it with another tex generator, and it worked just fine.
Two masses will impact, and they both hang on wires of 8.5 feet long. When both masses are hanging down, they are 1 inch apart. When I pull back one of the masses to impact the other, I need to exceed the 1 inch pullback, or the masses will not touch on the upswing. I need to compute the speed of the impact.
So, I pulled back the mass 3 inches, and it will swing through the 2 inch wide "dead zone" and then impact after exceeding 1 inch distance in the other direction. What is the velocity? I said that there is a transfer of potential energy to kinetic energy, and I used pythagorean's theorem to figure out the difference in heights.
Length of string (and hypotenuse) = always 8.5 feet.
Horizontal pullback distance = 7 inches
Energy difference = pullback at 7 inches - pullback at 1 inch
Thus, [itex]v = \sqrt_{\left(\sqrt_{8.5^2-(1/12)^2} - \sqrt_{8.5^2-(7/12)^2}\right)2g}[/itex]
This gets me a velocity of approximately 1.12 feet per second. Is this right? Also, for some reason, the tex integration isn't working for me anymore. It just draws a box around what I wrote. I checked it with another tex generator, and it worked just fine.
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