I Rented A Helicopter To Settle A Physics Debate

in 2014 the qualifying exam for the U.S physics team had this as question 19. a helicopter is flying horizontally at constant speed a perfectly flexible uniform cable is suspended beneath the helicopter air friction on the cable is not negligible so which of the following diagrams best shows the shape of the cable as the helicopter flies through the air to the right is it a hanging straight down B hanging diagonally to the left C this hook shape D the inverted hook shape or E kind of s Bend now apparently there's been a certain amount of controversy about the correct answer to this question so today we're going to go up in this helicopter and put this question to rest once and for all let's go a portion of this video was sponsored by Simply Safe which allowed us to rent this helicopter more about them at the end of the show I've got several thousand hours of carrying sling locks firebuck it's concrete buckets doing Powerline construction actual power poles you you name it anything needs to be moved around the mountains I've done biggest concern that I have is that the rope's going to interact with the rotor wash as it's interacting with the ambient air around the aircraft and we'll get a whipping action that falls down the rope and flips around on the end to a point that we worry if it will have a tendency to work its way back up towards the aircraft obviously we don't want it getting in the rotors or the tail rotor all right we're all set up [Music] here I'm deploying a battle rope like you'd see at the gym this one is about 15 meters long and it weighs 20 kilograms happy and win now the setup looks pretty simple but few people agree on what the right answer should be when I pulled YouTube the most common answer was C well done on making that beautiful bell curve by the way we got in touch with the questions author Professor Paul Stanley there were some creative students who actually constructed their own homemade scenarios one had a fan to the side and another fan blowing downwards so that they could mimic the motion of the helicopter and suspended a string and said oh it's this design and the faculty members looked at it then ...