Work Done By A General Variable Force

  • Thread starter Bashyboy
  • Start date
  • #1
1,421
5
As the title alludes to, I am currently reading about work. One sentence has left me very confused, thought: " Only the magnitude of this variable force changes, not its direction,
and the magnitude at any position does not change with time."
Could someone possibly help me understand this?
 

Answers and Replies

  • #2
mathman
Science Advisor
7,858
446
It seems to describe a particular force field, which is defined by two specific requirements. 1) It is constant over time. 2)The direction of the force is the same at all points in the field, but the magnitude varies with position.
 
  • #3
1,421
5
But it says "...and the magnitude at any position does not change with time," which would not be in accordance with the second requirement you provide. Anyways, I don't believe it is talking about force fields, because I have not read about those in my book yet.
 
  • #4
34,655
10,797
Take a simple, one-dimensional example: A force given by F=kx^2 where x is your position and k is some constant (like "1N/m^2").

Now, the direction is always the same (in positive x-direction), the magnitude at any position (fixed x) does not change with time, but the magnitude varies with the position (different x lead to different F).
You can use the same force, just in 3 dimensions. It always points in positive x-direction.
 

Related Threads on Work Done By A General Variable Force

  • Last Post
Replies
1
Views
3K
  • Last Post
2
Replies
39
Views
10K
  • Last Post
Replies
16
Views
4K
  • Last Post
Replies
6
Views
876
  • Last Post
Replies
1
Views
852
  • Last Post
Replies
20
Views
2K
  • Last Post
2
Replies
27
Views
3K
  • Last Post
Replies
2
Views
3K
  • Last Post
Replies
5
Views
951
  • Last Post
Replies
1
Views
693
Top