Tension Force?

  • Thread starter eraemia
  • Start date
  • #1
53
0

Homework Statement



A strong plank 8.0 m long and having a negligible mass is supported by steel cables from both ends. A jaguar with a weight of 800 N stands 2.0 m from one end. What is the tension force in the cable farthest from the jaguar?

a. 120 N
b. 200 N
c. 240 N
d. 400 N
e. 600 N
f. 800 N

Homework Equations





The Attempt at a Solution



I'm not sure how to solve this problem. Is it a two dimensional problem? I'm not told whether the bridge bends down because of the jaguar's weight. Now, to find the tension force, I know it's m times a, but since the jaguar is not moving, the jaguar's pull on the rope (the tension force) is only going to be the force of gravity which the jaguar experiences (in the -z direction). Is this then simply 800 N? But how do I take distances into account when calculating tension force? Thanks for any help.
 

Answers and Replies

  • #2
Astronuc
Staff Emeritus
Science Advisor
19,601
2,969
The problem is one of statics.

The sum of the tensions in the cables must equal that of the jaguars weight, but since the jaguar is asymmetrically positioned between the cables, one will bear more of the weight than the other.

To find the distribution of forces between the cables, pick one end and use the requirment that the sum of the moments about a pivot must equal zero.

Pick the end closest to the jaguar, and determine the moments. Take positive moment to cause counterclockwise rotation looking at the x,y plane.

Reference:
http://web.mit.edu/course/3/3.11/www/modules/statics.pdf
 

Related Threads on Tension Force?

  • Last Post
Replies
5
Views
802
  • Last Post
Replies
2
Views
556
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
1
Views
1K
  • Last Post
Replies
16
Views
5K
S
  • Last Post
Replies
1
Views
934
  • Last Post
Replies
3
Views
19K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
4
Views
1K
  • Last Post
Replies
11
Views
3K
Top