Adv Phy L15 February 4 with.notebook
February 04, 2011
A world's land speed record was set by Colonel John P. Stapp when in March 1954 he rode a rocket­propelled sled that moved along a track at 1020 km/h. He and the sled were brought to a stop in 1.40 s. In g units, what acceleration did he experience while stopping?
Feb 3­5:09 PM
Feb 4­9:19 AM
A fugitive tries to hop on a freight train traveling at a constant speed of 6.5 m/s. Just as an empty box car passes him, the fugitive starts from rest and accelerates at a = 3.0 m/s2 to his maximum speed of 8 m/s.
(a) How long does it take him to catch up to the empty box car?
Feb 4­9:23 AM
Feb 4­9:29 AM
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Adv Phy L15 February 4 with.notebook
Feb 4­9:34 AM
person who is properly restrained by an over­the­
shoulder seat belt has a good chance of surviving a car collision if the deceleration does not exceed 30 "g's" (1.00g = 9.80 m/s2). Assuming uniform deceleration of this value, calculate the distance over which the front end of the car must be designed to collapse if a crash brings the car to rest from 105 km/h.
Feb 4­9:39 AM
February 04, 2011
Feb 4­9:38 AM
A person jumps from a fourth­story window h = 14.8 m above a firefighter's safety net. The survivor stretches the net d = 1.6 m before coming to rest, see the figure.
(a) What was the average deceleration experienced by the survivor when she was slowed to rest by the net? Feb 4­9:43 AM
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