phy201
Your 'cq_1_17.2' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.
** **
Seed 17.2
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: ->->->->->->->->->->->-> :
If it act vertically downward it would have a 90degree angle???
The weight acts in the downward vertical direction, so its angle with horizontal would be 90 degrees.
However the x axis is not horizontal.
greater magnitude is the y component
#$&*
Using the definitions of the sine and cosine, find the components of the cart's weight parallel and perpendicular to the incline.
answer/question/discussion: ->->->->->->->->->->->-> :
x= 5cos(30deg)=.77
y= 5sin(30deg)= -4.94
The weight vector doesn't make an angle of 30 degrees with the positive x axis.
The formulas only apply if the angle is measured counterclockwise from the positive x axis.
Remember that quantities have units. 5 kg is the mass of the cart, but mass isn't a force. Its weight is the force exerted on it by gravity, and is 49 Newtons.
#$&*
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: ->->->->->->->->->->->-> :
not sure
the direction of force would be parallel.
#$&*
If no other force is exerted parallel to the incline, what will be the cart's acceleration?
answer/question/discussion: ->->->->->->->->->->->-> :
not sure how to work this.
** **
about 30 minutes
** **
I really dint know how to do this one, so Iknow I will have a revision.
&#Please compare your 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. &#