Mass on an accelerating truck with friction

  • Thread starter aemaggie
  • Start date
  • #1
1
0
http://www.smartphysics.com/Content/Media/Images/Mechanics/06/acceleratingtruck.png [Broken]

A box rests on top of a flat bed truck. The box has a mass of m = 24.0 kg. The coefficient of static friction between the box and truck is μs = 0.84 and the coefficient of kinetic friction between the box and truck is μk = 0.69.

3) What is the maximum acceleration the truck can have before the box begins to slide?
The answer is 8.23 m/s^2

4) Now the acceleration of the truck remains at that value, and the box begins to slide. What is the acceleration of the box?

The answer is 6.762
I did ukmg=ma but i don't understand why kinetic friction is the only force acting on the box.
 
Last edited by a moderator:

Answers and Replies

  • #2
35,388
11,731
Kinetic friction is the only horizontal force (as you neglect air resistance and so on). Which other forces do you expect?
 

Related Threads on Mass on an accelerating truck with friction

Replies
1
Views
2K
Replies
6
Views
2K
  • Last Post
Replies
1
Views
1K
Replies
21
Views
23K
Replies
4
Views
5K
  • Last Post
Replies
3
Views
2K
  • Last Post
2
Replies
25
Views
7K
  • Last Post
Replies
24
Views
10K
Replies
23
Views
30K
  • Last Post
Replies
14
Views
4K
Top