Unit 3 Assignment 1: momentum and energy 1. An ice-skater is twirling with her arms extended a. If she were to close her hands the momentum to her twirling will increase with less resistant from hands being extended picking up wind resistant’s. b. Then energy that was resistant with the hands extended transfers to the body momentum its twirl conserving its energy as she spins.
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14. A woman stuck in the middle of a friction-less ice pond can thrust her arms causing a momentum energy towards the direction she thrust towards. No friction below to stop the energy thrust direction to the shore.
36. The ke is at max at the start of its momentum left side. As PE will be at its equilibrium position which is it’s at its max, and reaches half at the end of its swing. Ke/pe
46. if the ball falls and there is air resistant the energy is then changed by other factors of energy. Now if the air wind was to be pushing the same direction then it would have a increase of KE. In which case if it is just there to resist then the ke is decreased depending if the ball doesn’t already have wings.
54. if two object have the same KE then the momentum is the same. Not applying the mass of the item nor having to include the environment. It both was to move with no other KE to resist then both would be going at same momentum whether is big or small.
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12. 150km skids 135m deceleration be a m/h^2. S2 / S1 = [V2/V1] ^2.
S2 = 15 *{150/ 50}^2 = 135 m v = 150, S = v^2/ 2a = 150^2 / (500/3) = (9 * 2500)* (3/500) = 27* 5 = 135