Kinetic friction

  • Thread starter mels
  • Start date
  • #1
2
0

Homework Statement



A car is moving with a speed of 20m/s when the brakes are applied. The wheels lock (stop spinning). After travelling 40m, the car stops. Determine the coefficient of kinetic friction between the tires and the road.

Homework Equations



Fk=uk x Fn

The Attempt at a Solution



I dont know how to encorporate the given into the equation !

Homework Statement





Homework Equations





The Attempt at a Solution

 

Answers and Replies

  • #2
There's another equation you need, one that puts all the given data together.
 
  • #3
You can apply simple formula...

calculate the acceleration 'a'... by
(square of final velocity)-(square of initial velocity)=2x a x distance

a=20x20/(2x40)
a=5

balance the force
uk x mass x g = mass x a
uk=a/g
uk=5/10=0.5
 
Last edited by a moderator:
  • #4
2
0
okay thank you ! i really appreciate it :)
 

Related Threads on Kinetic friction

  • Last Post
Replies
6
Views
17K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
6
Views
3K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
10
Views
1K
  • Last Post
Replies
4
Views
1K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
3
Views
2K
Top