1.A2kgrockisreleasedfromrestataheightof29m.Ignoreairresistanceanddeterminethekineticenergy,gravitationalpotentialenergy,andtotalmechanicalenergyateachofthefollowingheights:20m;15m;5m;9m.
2.Amanrunswithaspeedof6m/soffaplatformthatis10mabovethewater.Howfastifhemovingwhenhehitsthewater?Ignoreairresistance.
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