Center of Mass & Displacement Question

AI Thread Summary
The discussion focuses on calculating the displacement of the center of mass (CoM) for a system consisting of an olive and a Brazil nut under the influence of applied forces. The initial positions of the olive and nut are given, along with the forces acting on them. The user successfully calculated the initial CoM coordinates but is confused about how to proceed with finding the displacement after 5.6 seconds. They consider using the formula for displacement with acceleration but express uncertainty about the approach. The final advice suggests treating the initial CoM position as zero for calculating displacement due to constant acceleration.
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.
 
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