Cable car with 2 cable arrangement

  • Thread starter konglongjiqiche
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    Cable Car
In summary, the century-old ascensores in Valparaiso, Chile, are small cable cars that use a two-cable arrangement to go up and down steep hillsides. When one car ascends, the other descends using a system of two cables, one connecting the cars and the other pulled by a small motor. The tension in the connecting cable and the cable to the motor can be calculated using the mass of both cars (with passengers), the coefficient of rolling friction, and the constant speed at which the cars move. By drawing free body diagrams and taking into account the effects of gravity and rolling friction, the correct equations can be used to determine the tension in the cables. The cable to the motor is responsible for overcoming the
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konglongjiqiche
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Homework Statement


The century-old ascensores in Valparaiso, Chile, are small cable cars that go up and down the steep hillsides. As the figure(Figure 1) shows, one car ascends as the other descends. The cars use a two-cable arrangement to compensate for friction; one cable passing around a large pulley connects the cars, the second is pulled by a small motor. Suppose the mass of both cars (with passengers) is 1600 kg , the coefficient of rolling friction is 3.0×10−2, and the cars move at constant speed.

What is the tension in the connecting cable?
What is the tension in the cable to the motor?
https://session.masteringphysics.com/problemAsset/1383182/3/07.P43.jpg

Homework Equations


F=ma,since a=0, Fnet=0

The Attempt at a Solution


I drew a free body diagram on both of the cable cars, since F net=0, I was assuming that the x component of all the forces are 0, which are the rolling friction and the x component of the gravitational force. I also assumed that since both cars are 1600kg one's mass would be 800kg? with the rolling friction provided I thought the answer would be 0.03 cos 35 degree*m*g+sin 35 degree*m*g=T, but it seems to be incorrect.
Also I was just completely confused on the effect of the cable between the motor and one of the car. Does it pull the car up? although it appears on the picture that gravity from one car was pulling the other on up?
Thank you.
 
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  • #2
Look at it this way. If there were no friction, the cars would be completely balanced and a small nudge would get them moving one way or the other. With friction, the pull of the motor is needed to overcome just the friction but not gravity. It might be easier to see what's going on if you drew separate FBDs for the two cars.
 
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1. How does a cable car with 2 cable arrangement work?

A cable car with 2 cable arrangement works by using two cables, one for support and one for propulsion. The support cable is attached to the top of the car and runs along the entire length of the track, while the propulsion cable is connected to a motor at the bottom of the track. As the motor turns, it pulls the propulsion cable, which in turn moves the car along the track.

2. What are the advantages of a cable car with 2 cable arrangement?

One advantage of a cable car with 2 cable arrangement is that it can travel longer distances and over steeper inclines compared to a single cable system. The use of two cables also provides more stability and control for the car, making it safer for passengers.

3. How is the speed of a cable car with 2 cable arrangement controlled?

The speed of a cable car with 2 cable arrangement is controlled by the motor connected to the propulsion cable. By adjusting the speed of the motor, the car can be made to move faster or slower along the track.

4. What types of materials are used to make a cable car with 2 cable arrangement?

The support cable of a cable car with 2 cable arrangement is typically made of steel, while the propulsion cable is made of a durable material such as polyurethane. The car itself is usually made of lightweight materials such as aluminum or fiberglass.

5. Are there any safety features in place for a cable car with 2 cable arrangement?

Yes, there are several safety features in place for a cable car with 2 cable arrangement. These can include emergency brakes, backup power systems, and regular maintenance and inspections to ensure the safety and functionality of the cables and car. Additionally, passengers are required to wear safety restraints while riding the car.

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