Question

Problem three: An electrician is suspending a traffic light between two poles using cables as shown. Three physics students who are watching make the following contentions: Cable A Anders: “For this arrangement, the tension has to be the same in both cables, since they each support half the weight of the traffic light." Baji: "I think the tension in the left cable has to be larger because it is Cable B more vertical. The vertical component of its tension has to be larger than for the right-hand cable." Caitlin: "I think the tension in the left cable actually has to be less than the tension in the right cable. It is pulling more vertically, so it has an easier job of lifting its half of the traffic light. The cable on the right still has to lift its half, but since it is mostly pulling horizontally it has to have a really large tension to get a large enough vertical component." Which, if any, of the students do you think is correct? Anders Baji Caitlin None of them Explain. 18

Answer 1

Solution T los o ll I losa AL t T, sino Tosind mg T, sino al sina Equating the funisontal forces o is smaller than a sino will be smaller than sind ] Tz Sin@ Iz will be string of hans, [: 1 - sing which means Tension. In cable A will be larger than the Tension in cable B. Reasoning given by given by Baji is the correct one