Calculating Tension Force: Cable Cars in San Francisco

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SUMMARY

The tension force in the cable car's cable is directly related to the weight of the 2000kg block attached to the tensioning pulley. Given that the cable is not accelerating, it can be treated as fixed, meaning the tension in the cable equals the gravitational force acting on the block, calculated as 2000kg multiplied by the acceleration due to gravity (9.81 m/s²), resulting in a tension of approximately 19620 Newtons. The additional details regarding the cable's speed of 9.5 mph, its stretching of 100ft, and the diameter of the tensioning pulley are not necessary for calculating the tension force in this scenario. The tension felt by the cable car's cable is equal to the force applied by the block, not half, as the cable is not divided between two cables.

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Question:
The cable cars in San Francisco are pulled along their tracks by an underground steel cable that moves along at 9.5mph. The cable is driven by large motors at a central power station and extends, via an intricate pulley arrangement, for several miles beneath the city streets. The length of the cable stretches by up to 100ft during its lifetime. To keep the tension constant, the cable passes around a 1.5 m diameter "tensioning pulley" that rolls back and forth on rails, as shown in the diagram <http://img245.imageshack.us/img245/1350/cablecarib9.jpg>. A 2000kg block is attached to the tensioning pulley's cart, via a rope and pulley, and is suspended in a deep hole. Q:What is the tension in the cable car's cable

My question is:
1. Since the cable is not accelerating can it be treated as if it is just fixed?
2. Is the 9.5 mph, 100ft stretching and the diameter of the pulley relevant information. It seems to me that most of that is not necessary to solving this problem.

When i first attempted to solve this it seemed that the tension force that the cable would be feeling would be equal in magnitude to the force applied to the cable car by the 2000kg block. Is this reasoning correct?
 
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Any help would be very appreciated :)

Edit:(had a thought)

Would the tension that the cable car's cable would feel be half that of the total force being applied to the cable car since it is being essentially between two cables?
 
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