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Find the magnitude of the net force acting on this object

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1. The problem statement, all variables and given/known data
A 3.00 Kg object is moving in a plane, with its x and y coordinates given by x=5t^2-1 and y=3t^3+2, where x and y in meters and t in seconds. Find the magnitude of the net force acting on this object at t=2.00 secs.


2. Relevant equations



3. The attempt at a solution
Would you just substitute T in the equations to find the displacement of the object and then sum all the forces? I do not know how to sum the forces after I get the free body diagram drawn. Any tips??
 

nicksauce

Science Advisor
Homework Helper
1,272
5
You do not need a free body diagram. F = ma. You want F, you know m, can you find a?
 
Alright, so you use the distance it traveled to find the acceleration correct? Then as soon as you have that all you would need is Mass times acceleration to get force, but you have two separate acceleration one in the x and one in the y correct?
 
Since you have the position formulas for x and y could you do the derivative of that to get your velocity and then derivative of that to get your acceleration? Then you would have it? Or am I off base?
 

nicksauce

Science Advisor
Homework Helper
1,272
5
Since you have the position formulas for x and y could you do the derivative of that to get your velocity and then derivative of that to get your acceleration? Then you would have it? Or am I off base?
Yes, that is how you should approach the problem.
 

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