How Do You Calculate Force and Direction in Particle Motion Problems?

AI Thread Summary
To calculate the force and direction in particle motion problems, start by applying Newton's second law, F=ma, where m is the mass of the particle and a is its acceleration. The particle's motion is defined by the equations x(t) and y(t), which can be differentiated to find velocity and acceleration. At t=0.700s, determine the net force's magnitude and angle relative to the x-axis by using vector addition of the forces derived from acceleration. Understanding the relationship between net force and acceleration is crucial for solving these types of problems. Properly applying these principles will clarify the calculations needed for the particle's motion.
Rose15
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Member advised to use the homework template for posts in the homework sections of PF.
A 0.340 kg particle moves in an xy plane according to x(t)=-15.00+2.00t-4.00t^3 and y(t)=25.00+7.00t-9.00t^2, with x and y in meters and t in seconds. At t=0.700s, what are a.) the magnitude and b.) the angle (relative to the positive direction of the x axis) of the net force on the particle, and c.) what is the angle of the particle's direction of travel.

-My first post! I got stuck on this question because I wasn't sure exactly where to start because it doesn't seem to really follow the format of any of the questions we have done in class and so I am having a hard time understanding it.
 
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The first two questions are about the net force on the particle. What is the definition of net force ?
 
slider142 said:
What is the definition of net force ?
I suspect that's not what you meant to ask. The definition of net force is of no interest here. It is the consequence of the net force that matters, i.e. Newton's second law.
 
Rose15 said:
A 0.340 kg particle moves in an xy plane according to x(t)=-15.00+2.00t-4.00t^3 and y(t)=25.00+7.00t-9.00t^2, with x and y in meters and t in seconds. At t=0.700s, what are a.) the magnitude and b.) the angle (relative to the positive direction of the x axis) of the net force on the particle, and c.) what is the angle of the particle's direction of travel.

-My first post! I got stuck on this question because I wasn't sure exactly where to start because it doesn't seem to really follow the format of any of the questions we have done in class and so I am having a hard time understanding it.
You might be asked by a mentor to use the homework template and show your attempt first.
Basic vector addition and F=manet is all you need.
 
cnh1995 said:
You might be asked by a mentor to use the homework template and show your attempt first.
Basic vector addition and F=manet is all you need.
Fnet=ma
 
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