Sandy is training to spend time on the International Space Station by learning to walk on a platform floating in a pool of oil. The platform has a mass of 110 kg. is 5.00 m long, and floats on the oil without any friction. Sandy, with all her gear on, has a total mass of 65.0 k g. We consider "the system" to consist of Sandy and the platform.
a. The platform is initially tethered 1.00 m away from the rigid end of the pool. Sandy is initially at the left end of the platform, and walks with a constant velocity of 4.00 m/s towards the right. What is the kinetic energy of the system when Sandy reaches the right end of the platform?
b. The tether is now untied so that the platform floats freely on the oil, starling 1.00 m way from the rigid end of the pool. Sandy again starts at the left end of the platform and walks right with a constant velocity of 4.00 m/s relative to the platform. Now what me kinetic energy of the system when Sandy reaches the right end of the platform?
c. If there's a difference in your answers between Parts a and b, explain why that is so. Where did the energy go?
d. When Sandy reaches the right end of the platform in part b, how far away is the platform from the right end of the pool?
e. Sandy is now given a 10.0 kg lead weight to throw. On land, She can throw it 4.50 m. If she again stands at the left end of the untethered platform and throws the weight to the right, exactly where docs it land relative to the right end of the platform?
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