Worked Example 03
The Question
You have a summer job working in Woden washing windows on office blocks (the pay is great and so are the views). The platform you and your partner are using to get to the windows is a meter wide and four meters long. You know from hauling the platform out of your truck countless times that it has a mass of 70 kg. It is supported by two cables, one at each end, mounted on-center to prevent the platform from tipping over as it is pulled up the side of the building at a constant speed. If you (mass of 55 kg) are standing on the platform 1 meter from one cable while your partner (mass of 87 kg) is 1.3 meters from the other cable and both of you are half a meter from the side, what is the tension in each cable? Assume the platform has a uniform mass distribution and is of negligible thickness.
The Answer
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