Calculating Tension Force in a Tug-of-War

[temaire]

Homework Statement

The diagram below shows two people having a tug-of-war. Determine the unknown tension force if person A is winning.

http://img80.imageshack.us/img80/8286/forcefp2.gif​

Homework Equations

None that I think are necessary.

The Attempt at a Solution

I think that the unkown tension for person B would be 900 N, because tension is constant throughout the entire rope.

 

[learningphysics]

You're right if the rope is massless... do they give a mass for the rope?

 

[stewartcs]

Homework Equations

None that I think are necessary.

How about Fnet = ma?

The Attempt at a Solution

I think that the unkown tension for person B would be 900 N, because tension is constant throughout the entire rope.

Typically, since the mass of the rope is negligible compared to the rest of the system we assume it to be massless. If so, then the tension throughout the rope is indeed the same (of course if it has mass and is not accelerating then you get the same result as well).

In this case, since A is winning, the rope would be accelerating (unless A is winning at a constant velocity!). However, since the rope is assumed massless then the tension is the same throughout as previously stated.

 

[temaire]

No, they don't give a mass for the rope. Thanks for the help though guys.