Drag Force

  • #1

Homework Statement


A baseball is thrown straight up. The drag force is proportional to v^{2}.
In terms of g, what is the y-component of the ball's acceleration when its speed is half its terminal speed and it is moving up? In terms of g, what is the y-component of the ball's acceleration when its speed is half its terminal speed and it is moving back down?

Homework Equations



v terminal = [tex]\sqrt{mg/D}[/tex]

The Attempt at a Solution


I honestly have no idea how to attempt this problem
 

Answers and Replies

  • #2
671
2
The drag force is of the form:
[tex]F_d = -kv^2[/tex]

Or to use your notation:
[tex]F_d = -Dv^2[/tex]

The terminal velocity is achieved when the ball starts falling at a constant velocity. At that point, the following holds true:
[tex]kv^2=mg[/tex]
 
  • #3
tiny-tim
Science Advisor
Homework Helper
25,836
252
I honestly have no idea how to attempt this problem

Hi clarineterr! :wink:

Start "acceleration = dv/dt = … " :smile:
 

Related Threads on Drag Force

  • Last Post
Replies
5
Views
6K
  • Last Post
Replies
6
Views
1K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
3
Views
871
  • Last Post
Replies
17
Views
5K
  • Last Post
Replies
9
Views
3K
  • Last Post
Replies
1
Views
202
  • Last Post
Replies
3
Views
1K
  • Last Post
Replies
6
Views
1K
Top