Seed 172

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course Phy 121

re-submit

A 5 kg cart rests on an incline which makes an angle of 30 degrees with the horizontal. •Sketch this situation with the incline rising as you move to the right and the cart on the incline. Include an x-y coordinate system with the origin centered on the cart, with the x axis directed up and to the right in the direction parallel to the incline.

The gravitational force on the cart acts vertically downward, and therefore has nonzero components parallel and perpendicular to the incline.

Sketch the x and y components of the force, as estimate the magnitude of each component.

What angle does the gravitational force make with the positive x axis, as measured counterclockwise from the positive x axis? Which is greater in magnitude, the x or the y component of the gravitational force?

answer/question/discussion:

When I sketched a graph, I had a x-y axis. On (0, 0), I placed the beginning of the incline. I had the incline rising in the direction of positive x with a 30 degree incline. I placed the cart at the beginning of the incline (0,0).

vx = magnitude * cos (30 degrees)

vy = magnitude * sin (30 degrees)

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• Using the definitions of the sine and cosine, find the components of the cart's weight parallel and perpendicular to the incline.

answer/question/discussion:

wt = m * g

wt = 5 kg * 9.8 m/s^2

wt = 49 kg per meters/squared seconds

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• How much elastic or compressive force must the incline exert to support the cart, and what is the direction of this force?

answer/question/discussion:

PE elastic = .5 * k * x^2

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• If no other force is exerted parallel to the incline, what will be the cart's acceleration?

answer/question/discussion:

It would be similar to gravity.

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"

Your first answer was about velocity rather than force. The gravitational force is verically downward, not at a 30 degree angle to the positive x axis.

Note that you should use the form for the individual 'seed' question, in order to be sure you're provided with the correct link. If you haven't correctly identified the problem, the link will be wrong. However I expect you've identified it accurately, so the link should work.

There is no need for a revision, but be sure you understand the discussion at the link.

&#See any notes I might have inserted into your document, and before looking at the link below see if you can modify your solutions. If there are no notes, this does not mean that your solution is completely correct.

Then please compare your old and new solutions with the expanded discussion at the link

Solution

Self-critique your solutions, if this is necessary, according to the usual criteria. Insert any revisions, questions, etc. into a copy of this posted document. Mark any insertions with &&&& so they can be easily identified.

If your solution is completely consistent with the given solution, you need do nothing further with this problem. &#

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