Tension (Conceptual Misunderstanding?)

[Glenn900]

This one comes from an SAT II Physics review book.

Homework Statement

During a company picnic, 6 accounting department workers participate in a tug of war with 6 sales force personnel. Each team pulls on the rope with 1200N of force. What is the tension in the rope?

a) 2400N
b) 1200N
c) 600N
d) 200N
e) 100N

The Attempt at a Solution

Consider the situation where one side of the rope is attached to a wall or other stationary object. With a team of workers pulling on the rope with 1200N, the tension would then be equal to 1200N. With workers on both sides pulling with 1200N, the combined tension in the rope should then be 2400N.

The answer to this problem states that the correct answer is B, but then goes on to explain: The tension in a rope is the same throughout. Both teams must pull with a force of 1200N to maintain static equilibrium, so the total tension is 2400N.

Is this just a bad review book with an incorrect answer choice, or is there something I'm missing?

 

[radou]

The answer is 1200 N, but if by "so the total tension is 2400N." the book meant "the sum of the tensions", then it is not correct, the sum is 0, since the reaction force is equal in magnitude and opposite in direction, just the same as you had the rope attached to a wall. In any case, the answer is 1200 N.