What is the speed and tension of a wave pulse on a ski gondola cable?

AI Thread Summary
The discussion focuses on calculating the speed and tension of a wave pulse in a steel cable used for a ski gondola. The cable is 620 meters long, and a wave pulse takes 16 seconds for a round trip, leading to a calculated speed of approximately 78.12 m/s. The frequency is determined to be 0.063 Hz based on the period of the pulse. The mass per unit length of the cable is found to be 1.39 kg/m, which is essential for calculating tension. The conversation emphasizes the importance of using the correct properties of steel and the wave equation to derive these values accurately.
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Homework Statement



a ski gondola is connected to the top of a hill by a steel cable of length 620m and diameter 1.5cm (r=.015m) As the gondola comes to the end of its run it bumps into the terminal and sends a wave pulse along the cable. It is observed that it took 16 s for the pulse to return a. what is the speed of the pulse? what is the tension in the cable?

Homework Equations


v=\lambda*f
v=\sqrt{F/(m/L)}
f=1/T

The Attempt at a Solution


how would I relate the length and diameter to mass of the cable? I think I'm missing an equation, but all the others seem to be for springs or pendulums. If the period is 16 seconds, then I would have frequency as .063Hz and I could just use twice the length of the cable, for a full wave? Am I headed in the correct direction?
 
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Hi 0338jw,

They say the cable is made of steel; what property of steel could you look up that relates mass and the dimensions of the cable?

The pulse took 16 seconds to travel from the end, to the beginning, and back to the end. How far did it go in those 16 seconds? Then what would the speed be?
 
so when I find mass per unit length using mass per unit length and density I get 1.39 kg/m. I solved for frequency and I got .063 Hz. When I used wave equation for speed with 2* 620m because it had to go back and forth I get 78.12m/s. Is this correct? I'm going on to find the tension using this value
 
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