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# A constant acceleration equation implies that so

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Unformatted text preview: acceleration equation implies that so Alternative approach: The total work done by friction going up and down the board is (the same work up and down) and gravity is a conservative force (zero work on the round trip), so by the Work-Energy theorem, Thus, . Solving for the final speed gives 2. [13pt] If a box of mass 5.50 kg is set on a large spring, it compresses the spring a distance 11.0 cm from its equilibrium position. (a) [7pt] Suppose the same box is now lifted to a height above the top of the uncompressed spring and dropped on it, compressing the spring a distance 44.0 cm (so that From what height was the box dropped? The fact that the box sits at rest on the spring with compression implies that the forces balance there, so if is the spring constant. If the box is dropped from height above the uncompressed spring, and the gravitational energy is taken to be zero at the top of the uncompressed spring, energy conservation implies Then (11.0 cm) cm. 3 Note: The mass was not needed in the problem, but giving it permits an alternative solution in which 490 N/m is obtained first. Then, when the spring...
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## This document was uploaded on 03/09/2014 for the course PHYS 221 at Ohio Northern University.

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