Center of Mass & Displacement Question

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ChazyChazLive
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Homework Statement


A big olive (m = 0.051 kg) lies at the origin of an xy coordinate system, and a big Brazil nut (M = 0.56 kg) lies at the point (0.81, 3.0) m. At t = 0, a force Fo = (2.6 + 1.7) N begins to act on the olive, and a force Fn = (-4.4 -3.4) N begins to act on the nut.


Homework Equations


What is the (a)x and (b)y displacement of the center of mass of the olive-nut system at t = 5.6 s, with respect to its position at t = 0?


The Attempt at a Solution


Okay, so far, I found X center of mass, and Y center of mass. (0.742,2.75)
I don't know what to do afterwards.
I tried combining the forces, resulting in a Fnetx and Fnety.
So... now... me lost >.< Can someone give me a little help please.
 
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If you have the net force resolved in x,y and the total mass, then doesn't that determine the acceleration in x,y of the CoM?
 
Yes, so.. er this is where I get confused.
Should I just stick the acceleration in x and y into the formula
x = x0 + .5at^2 ?? with the x being the 0.742 and then 2.75 to find the final x,y?
It sounds right but I just seem to doubt it.
 
ChazyChazLive said:
Yes, so.. er this is where I get confused.
Should I just stick the acceleration in x and y into the formula
x = x0 + .5at^2 ?? with the x being the 0.742 and then 2.75 to find the final x,y?
It sounds right but I just seem to doubt it.

I'd forge ahead.

Since they want displacement of the center of mass, whatever the initial position of the CoM when the olive-nut salad was at rest would be 0 for purposes of calculating displacement of CoM from the constant acceleration.