What Is Sam's Top Speed and Travel Distance on Jet Powered Skis?

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Sam, weighing 80 kg, uses jet-powered skis with a thrust of 189N and a kinetic friction coefficient of 0.1, which run out of fuel after 12 seconds. The top speed achieved by Sam is calculated to be 16.578 m/s. To determine the distance traveled before coming to a stop, the initial calculations yielded an incorrect displacement of 198.936 m. The correct approach involves equating the work done by friction to the kinetic energy of the skier. This discussion emphasizes the importance of applying the right physics equations to solve for speed and distance in motion scenarios.
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Homework Statement



Sam, whose mass is 80 kg, takes off across level snow in his jet powered skis. The skis have a thrust of 189N and a coefficient of kinetic friction on snow of 0.1. Unfortunately, the skis run out of fuel after only 12s. a.) What is Sam's top speed? b.) How far has Sam traveled when he finally coasts to a stop?

Homework Equations



Fk = uk(n)
F=ma

The Attempt at a Solution


I solved part A by using F-uk(n) = m(Ax). I solved for Ax, and got the answer to be 1.3815. I then used acceleration = velocity/time to find the velocity. I got the velocity to be 16.578, which is right. For part B I tried using Vxf^2 = Vxi^2 + 2(Ax)(delta x) to find the change in displacement. I got 198.936m, which was wrong.
 
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For the second part use the fact that
Frictional_force x distance = work_done_to_stop_skier = kinetic_energy_of_skier.
 

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