What is the velocity of the body

  • Thread starter Thread starter nmegabyte
  • Start date Start date
  • Tags Tags
    Body Velocity
Click For Summary

Homework Help Overview

The discussion revolves around a physics problem involving a body moving along the positive x-axis under the influence of a varying force, specifically Fx = -6x N. The initial conditions include the mass of the body and its velocity at a specific position. Participants are tasked with determining the velocity at another position and the position at which the velocity reaches a certain value.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to connect work and kinetic energy to solve the problem, expressing uncertainty about how to combine these concepts effectively. Some participants suggest using Newton's second law to derive a relationship for velocity, questioning how to apply the varying force in this context.

Discussion Status

The discussion is ongoing, with participants exploring different approaches to relate force, work, and velocity. Some guidance has been offered regarding the application of Newton's second law, but there is no explicit consensus on the method to proceed.

Contextual Notes

Participants are navigating the complexities of a varying force and its implications on motion, with some expressing confusion about the relationships between the physical quantities involved. The problem context includes specific values and conditions that may influence the discussion.

nmegabyte
Messages
15
Reaction score
0
The only force acting on a 3.4 kg body as it moves along the positive x-axis has an x component Fx = - 6x N, where x is in meters. The velocity of the body at x = 3.0 m is 8.0 m/s.

a) What is the velocity of the body at x = 4.0 m? m/s

(b) At what positive value of x will the body have a velocity of 5.0 m/s?
i have some kinda idea but it may not be clear
so i started with using a Formula for work since its moving along positive x direction
W=Fd cos(angle)
and kinetic energy is
K=1/2mv^2
thats all i can think off for the beginning
Plz just give me some hint how to combine these 2 formulas since angle between force and direction is 180 it will be cos180
 
Physics news on Phys.org
Your force is varying with x.

So if the only force acting is Fx= 6x, can you use Newton's second law to find an expression for velocity?

(Hint: dv/dt = dv/dx * dx/dt)
 
still don't get it
 
nmegabyte said:
still don't get it

F= ma

-6x = ma
 

Similar threads

Resistance force changing the velocity of an object
  • · Replies 8 ·
Replies
8
Views
1K
Two body problem, velocities of two bodies, relative velocity given
  • · Replies 9 ·
Replies
9
Views
2K
Motion of an Object: Displacement & Average Velocity
  • · Replies 8 ·
Replies
8
Views
2K
How do I derive an expression for the velocity vector for any α?
  • · Replies 26 ·
Replies
26
Views
4K
Center of mass and momentum- A question about systems
  • · Replies 25 ·
Replies
25
Views
2K
Free Body Diagram of Mass-Spring System
  • · Replies 5 ·
Replies
5
Views
2K
Kinetic energy transfer from a rotating body in an inelastic collision
  • · Replies 23 ·
Replies
23
Views
3K
Which block reaches the wall faster?
  • · Replies 2 ·
Replies
2
Views
1K
Body Velocity and Position on X-Axis at a Given Moment
  • · Replies 4 ·
Replies
4
Views
1K
Relative Velocity and Angles of Movement (Sears & Zemansky's Exercise)
  • · Replies 11 ·
Replies
11
Views
3K