Finding force and equation of motion

AI Thread Summary
The discussion revolves around finding the force and equation of motion for a particle with the velocity function v(x) = ax - 2, specifically when x = a. Participants clarify that the motion occurs on a horizontal frictionless plane and attempt to derive the force using F = m dv/dt. The integration of force leads to potential energy, but the challenge remains in determining the motion of the particle over time. A suggestion is made to solve the separable differential equation dx/dt = ax - 2 to find the motion as a function of time. The conversation emphasizes the need to specify velocity and acceleration at the given position to fully describe the motion.
Jared Hill
Messages
3
Reaction score
0

Homework Statement


If v(x)=ax-2, then what is its force in terms of x. What is its motion as a function of time when x=a?

Homework Equations

The Attempt at a Solution

 
Physics news on Phys.org
What is v(x)? The motion of what are you speaking about?
Show the relevant equations and your attempt to solve the problem.
 
ehild said:
What is v(x)? The motion of what are you speaking about?
Show the relevant equations and your attempt to solve the problem.
It is the motion along a horizontal frictionless plane. I did F=m dv/dt= m dv/dx*dx/dt= -2ma2x-5
Then I fould potential energy by integration. However I could not find the motion of the particle.
 
Jared Hill said:
It is the motion along a horizontal frictionless plane. I did F=m dv/dt= m dv/dx*dx/dt= -2ma2x-5
Then I fould potential energy by integration. However I could not find the motion of the particle.
How do you specify the motion of a particle at a given time or at a given place? You give the velocity and acceleration. What are they at x=a?
 
ehild said:
How do you specify the motion of a particle at a given time or at a given place? You give the velocity and acceleration. What are they at x=a?
Sorry for the incomplete question.
If the particle starts at the position x = a, find its motion as a function of time.
 
You know that v=dx/dt. You have the equation dx/dt=ax-2 This is a very simple separable differential equation. Can you solve?
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'Calculation of Tensile Forces in Piston-Type Water-Lifting Devices at Elevated Locations'
Figure 1 Overall Structure Diagram Figure 2: Top view of the piston when it is cylindrical A circular opening is created at a height of 5 meters above the water surface. Inside this opening is a sleeve-type piston with a cross-sectional area of 1 square meter. The piston is pulled to the right at a constant speed. The pulling force is(Figure 2): F = ρshg = 1000 × 1 × 5 × 10 = 50,000 N. Figure 3: Modifying the structure to incorporate a fixed internal piston When I modify the piston...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top