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The Crash of Skylab NASA’s Skylab, the largest spacecraft ever to fall back to the Earth, reentered the Earth’s atmosphere on Jury 11, 1979, and broke into a myriad of pieces. One of the largest fragments was a 1770-kg, lead-lined film vault, which landed with an estimated speed of 120 m/s If its speed at an altitude of 143 km was 7950 m/s how much nonconservative work was done on the film vault during reentry?
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- The Crab Nebula (see Figure 7.41) pulsar is the remnant of a supernova that occurred in A.D. 1054. Using data from Table 7.3, calculate the approximate factor by which the power output of this astronomical object has declined since its explosion.arrow_forwardIn 1990, Walter Arfeuille of Belgium lifted a 281.5-kg object through a distance of 17.1 cm using only his teeth. (a) How much work was done on the object by Arfeuille in this lift, assuming the object was lifted at constant speed? (b) What total force was exerted on Arfeuilles teeth during the lift?arrow_forwardGive an example of a situation in which there is a force and a displacement, but the force does no work. Explain why it does no work.arrow_forward
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