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1. What is the initial kinetic energy of the skier? What is the final kinetic en

ID: 1972849 • Letter: 1

Question

1. What is the initial kinetic energy of the skier? What is the final kinetic energy of the skier?

The only hint that it gave me was the kinetic energy of an object of mass (m) and moving at velocity (v) is given by the equation K= (1/2)m(v^2)

PLEASE HELP!

Marjan, a skier of mass (m) , coasts a distance on level snow to a stop from a speed of (v) , as depicted in the figure. Use the work-energy principle to find the coefficient of kinetic friction (uk) between the skis and the snow. 1. What is the initial kinetic energy of the skier? What is the final kinetic energy of the skier? The only hint that it gave me was the kinetic energy of an object of mass (m) and moving at velocity (v) is given by the equation K= (1/2)m(v^2) PLEASE HELP!

Explanation / Answer

The work is done by friction (negative work) to slow theskiier down to a stop. The only horizontal force is thefriction in the backward direction, and her momentum in the forwarddirection is not a force. So pick diagram 'B' According to work-energy theorum:   WFf =KE                                                       -Ff s = 0 - 1/2 m v2                                                                        um g s = 1/2 mv2        cancel them's                                                     2 u g s   = v2                                                           u    = v2 / 2 gs                                                           u    = v2 / 2 gs