physics help
posted by Anonymous .
A ski gondola is connected to the top of a hill by a steel cable of length 680 m and diameter 1.7 cm. 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 15 s for the pulse to return. What is the speed of the pulse? AND What is the tension in the cable? I thought part 1 was t=distance/speed but the answer was not correct. Please help!

Part one is asking for the speed of the pulse. The equation for speed is v = d/t (or v = s/t depending on your textbook. Velocity = Distance/Time. Since the pulse is traveling from the terminal to the other side, and back to origin, you must take double the distance of the rope. So you are looking at the equation: v = 1360m/15s (since 15s is how long it takes for the pulse to travel from and to the origin.) So the answer to the first part is 90.66 m/s. Part II im still working on, sorry.