Help Physics Car Coast problem?

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http://www.physicsclassroom.com/class/vectors/Lesson-3/Inclined-Planes

If you go to the website above, you will see a drawing of an object that is on an inclined plane. The following equation is used to determine the force that causes the object to accelerate as it slides down the inclined plane.

Force parallel = m * g ** sin θ
a = g * sin θ

In the problem that you have, the car is moving up the inclined plane. This means the force will cause the car to decelerate. You can use the following equation to determine the distance the car moves up the slope before starting to roll back down.

vf^2 = vi^2 + 2 * a * d, vf = 0, a = -9.8 * sin 9
0 = 23^2 + 2 * -9.8 * sin 9 * d
19.6 * sin 9 * d = 529
d = 529 ÷ (19.6 * sin 9)

This is approximately 172.5 meters. I hope my explanation and the drawing at the website help you understand how to solve this type of problem. If you still have some questions, you can contact me the following email address.

morrison60957@yahoo.com...Show more

Let x = vertical distance gained

h = distance up the plane

Then

x/h = sin(9)

x = hsin(9)

Using the conservation of energy

Kinetic energy at the foot of the plane is equal to the potential energy gained

KE = 1/2m v^2 and PE = mg(hsin(9))

Therefore

1/2mv^2 = mghsin(9)

1/2 v^2 = ghsin(9)

h = (1/2v^2)/gsin(9)

= (1/2*23^2)/9.8sin(9)

= 172.53 m

Does it deserve best answer?...Show more

If you don't get the sine cosine things, then why are you taking physics? Why does your school even allow such a thing? It's early in the term; transfer to another curriculum, one that does not require basic trig....Show more

I can't understand a lick of what you're saying. Try using some commas....Show more