Question

Our 70 kg heroine is two-thirds of the way across a horizontal 30 m long bridge over a canyon with perfectly vertical walls. The bad guys then cut the supports of the bridge (she is closer to where the supports are cut than the other side). The bridge, which can be modeled as a rod of mass 500 kg and uniform density, then begins to rotate downwards with our heroine clinging to it. How fast is the heroine traveling in m/s when she hits the canyon wall?

Answer 1

This was the case A standard action movie scene is the following: the hero or heroine is on a bridge when the most devious evil bad guys cut the supports on one side of the bridge, leaving the hero/heroine to cling desperately to the bridge as it slowly swings down. Then there's the camera shot over the side of the cliff as we wait to see if the hero or heroine actually held on to the bridge and is now climbing back up.

Answer 2

use conservation of energy to solve this question
take the centre of mass of the heroine and bridge and take the loss in gravitational potential energy to be converted to rotaional kinetic energy.

Answer 3

thanx bro for helping bt i have alread solved it and got an answer of 19.8 mps