How Fast and Far Can Jet Powered Skis Go?

In summary, Sam, with a mass of 80kg, travels on jet powered skis with a thrust of 189N and a coefficient of kinetic friction on snow of 0.1. After 12 seconds, the skis run out of fuel. The question asks for Sam's top speed and the distance traveled before coming to a stop. Using the equations F=ma and kinematic equations, it was found that Sam's acceleration was 1.3815 m/s^2 and his final velocity was 16.578 m/s. Part B of the problem, involving coasting to a stop, is still being solved.
  • #1
aligass2004
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Homework Statement



Sam, whose mass is 80kg, 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. Unfortuneately, the skis run out of fuel after only 12s.

Homework Equations


F=ma
kinematic equations

The Attempt at a Solution


I have no idea where to even begin with this problem.
 
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  • #2
The problem statement is incomplete. What are you being asked to find?
 
  • #3
I'm sorry. The question wants to know what Sam's top speed is, and how far has Sam traveled when he finally coasts to a stop.
 
  • #4
OK, here are a couple of hints. This is a two part problem. The first part is the powered motion. Use your equations of motion to find the distance and velocity at the point where power quits and those are initial conditions for the 2nd part of the problem, which is coasting to a stop.

What are the relevant equations of motion? The need to involve mass, force, friction, etc. F=ma is a good start. Go a bit further. How does friction enter into the picture? If you haven't done it already, it REALLY helps to draw a picture and label the pertinent information.
 
  • #5
Here's some help if you're having trouble visualizing it.

untitled4.jpg
 
  • #6
Ok, I got part A by using F-uk(n) = m(Ax). I got the acceleration to be 1.3815. Using that I found the velocity, which is 16.578. I am having trouble figuring part B out. I tried using Vxf^2 = Vxi^2 + 2(Ax)(delta x).
 

FAQ: How Fast and Far Can Jet Powered Skis Go?

1. What is the difference between top speed and displacement?

Top speed refers to the maximum velocity of an object, while displacement refers to the change in position of an object over a certain period of time. Top speed is a measure of how fast an object can move, while displacement is a measure of how far an object has moved.

2. How is top speed measured?

Top speed is typically measured in units of distance per unit of time, such as miles per hour or kilometers per hour. In some cases, it may also be measured in units of acceleration, such as meters per second squared.

3. What factors influence top speed?

Top speed can be influenced by a variety of factors, including the power and efficiency of an object's engine or propulsion system, the aerodynamic design of the object, and external factors such as air resistance and surface friction.

4. How does displacement affect top speed?

Displacement does not directly affect top speed, as it is a measure of distance rather than speed. However, displacement can indirectly affect top speed by affecting the time it takes for an object to reach its top speed. For example, a larger displacement may require more time to accelerate to its top speed compared to a smaller displacement.

5. Can top speed be exceeded?

In theory, top speed can be exceeded if the object is able to overcome the limitations of its propulsion system and external factors such as air resistance. However, in practice, most objects are limited by their design and physical capabilities, and it is not recommended to exceed the designated top speed of an object.

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