Force required down an incline.

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To determine the force required to push a 22kg bobsled down a 6-degree incline to achieve a speed of 60 km/h over 75 meters, the coefficient of kinetic friction is 0.10. The acceleration needed was calculated using the equation v² = 2ax, resulting in an acceleration of 1.85 m/s². The force was then computed using F = ma, yielding a required force of 40.7 N, which matches the book's answer. Frictional force was also considered, calculated as 21 N. The discussion highlights the importance of correctly applying physics equations to solve the problem efficiently.
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Homework Statement


The co-efficient of kinetic friction for a 22kg bobsled on a track is 0.10. What force is required to push it down a 6 degree incline and achieve a speed of 60km/h at the end of 75m.


Homework Equations


Ffr=uFn
v^2=2a(x)
F=ma



The Attempt at a Solution


(65/3.6)^2=2a(75)
a=2.17ms^-2

F=ma
F=(22)(2.17)
F=47.8

Ffr=uFn=(0.10)(22)(9.8)sin6=21N
But then I am not sure what to do next?
 
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I think I may have been overthinking this problem
The sled is at rest so Ffr=mgcos
So force required is
(60/3.6)^2=2a(75)
a=1.85ms^-2
F=22x1.85=40.7N
Which is the answer in the book.
:mad: Can't believe I worked on this problem for about an hour.
 
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