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## Homework Statement

A 2.50kg object is moving on a plane with coordinates x=2t

^{2}-4 and y=3t

^{3}-3.

Find the magnitude of the net force at t=2.00s

## Homework Equations

[tex]\Sigma[/tex]F

_{y}= 0 (no movement on y axis)

[tex]\Sigma[/tex]F

_{x}= m*a (mass x acceleration)

## The Attempt at a Solution

Alright, first of all, nice to meet you all; this is my first post on the forum so by all means, if I'm doing something incorrectly, just let me know.

Conceptualize: Using the sum of the froces acting on x and the sum of the forces acting on y, I think I could find the magnitude of the net force with

|F|

^{2}= x

^{2}+y

^{2}

**1-**I figured it would be easier to draw the diagram of the forces by taking (x,y) coordinates at t=0 & t=2 (in order to see the direction of the incline). This one seems to be going from the 3

^{rd}quadran to the first.

**2-**I can then write my [tex]\Sigma[/tex]F

_{x}& [tex]\Sigma[/tex]F

_{y}equations like this:

[tex]\Sigma[/tex]F

_{y}= 0 = n - w

n = normal force

w = weight = mass x gravity(acceleration)

[tex]\Sigma[/tex]F

_{x}= m * (F sin [tex]\theta[/tex])

This is where I get confused.

Should I include a y component for the force in my y (F cos [tex]\theta[/tex])?

And what other forces are acting on my x axis??

P.S.: I seem to be having problems with the code @ point

**2-**; if you see a square root in front of Fx, ignore it, it's a SIGMA... I tried refreshing the page and all but I keep getting the sqr root in the preview ô.O

Same goes for F sin theta... it's obviously not F sin sigma...