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

Torque and Plank

  • Thread starter ramalik
  • Start date
  • #1
12
0
A uniform plank of length 5.2 m and weight 213 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 445 N walk on the overhanging part of the plank before it just begins to tip?

I know you have to set the torque of the plank equal to the torque of the man and solve for his lever length. I just dont know how to get the torque of the plank.
 

Answers and Replies

  • #2
Doc Al
Mentor
44,882
1,130
I just dont know how to get the torque of the plank.
Where does the weight of the plank effectively act?
 
  • #3
12
0
the center! so i have to find the difference between the center point and the piece hanging off the side?
 
  • #4
Doc Al
Mentor
44,882
1,130
Yes. Hint: Choose the right support as the pivot point for calculating torques. How far from that point is the center of mass of the plank?
 
  • #5
12
0
2.6-1.1 = 1.5 m. Thanks!
 

Related Threads for: Torque and Plank

  • Last Post
Replies
11
Views
9K
  • Last Post
Replies
4
Views
11K
  • Last Post
Replies
3
Views
697
  • Last Post
Replies
4
Views
19K
Replies
3
Views
4K
Replies
7
Views
914
Replies
22
Views
709
Top