• Support PF! Buy your school textbooks, materials and every day products Here!

Help with torque problem please

  • Thread starter wolfgarre
  • Start date
  • #1
2
0
Need help solving/setting up this problem for Physics:

A ladder of length L and weight W rests against a wall. The coefficient of static friction between the ladder and the floor and between the ladder and the wall is mu=0.5 What is the minimum angle the ladder can make with the floor (theta) without slipping?

What i know:
sum of torques = 0
sum of forces in y dir = 0
sum of forces in x dir = 0
forces in y dir = normal force from floor, friction with wall (mu times normal force from wall),and weight (W)
forces in x dir = friction with floor (mu times normal force from floor), normal force from wall

I have set the torque point at the ladder's contact with the floor and know there will be five equations to deal with.
If anyone could help me find these equations or help me set the problem up i'd appreciate it.

Jeff
 

Answers and Replies

  • #2
NateTG
Science Advisor
Homework Helper
2,450
5
The torque from a force is r sin α where r is the length of the level arm to the point where the force is applied, and α is the angle that the force makes with the arm.
 

Related Threads on Help with torque problem please

  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
1
Views
3K
  • Last Post
Replies
10
Views
22K
  • Last Post
Replies
4
Views
7K
  • Last Post
Replies
2
Views
1K
Replies
7
Views
8K
Replies
2
Views
1K
Top