A cameraman on a pickup truck is traveling westward at19 km/h while he videotape
ID: 1764199 • Letter: A
Question
A cameraman on a pickup truck is traveling westward at19 km/h while he videotapes a cheetah thatis moving westward 24 km/h faster than thetruck. Suddenly, the cheetah stops, turns, and then runs at 45 km/heastward, as measured by a suddenly nervous crew member who standsalongside the cheetah's path. The change in the animal's velocitytakes 1.8 s. (a) What is its acceleration from the prespective of thecameraman?(b) What is its acceleration from the perspective of the nervouscrew member?
A cameraman on a pickup truck is traveling westward at19 km/h while he videotapes a cheetah thatis moving westward 24 km/h faster than thetruck. Suddenly, the cheetah stops, turns, and then runs at 45 km/heastward, as measured by a suddenly nervous crew member who standsalongside the cheetah's path. The change in the animal's velocitytakes 1.8 s. (a) What is its acceleration from the prespective of thecameraman?
(b) What is its acceleration from the perspective of the nervouscrew member?
Explanation / Answer
Using eastward as negative direction!!! to camera man looks like cheetah is moving at 64 km/hr when moves eastward so change in velocity to him is -64-24= -84 km/hr your acceleration for cameramn is -84 km/hr/ (1.8 s) be sure and convert your km/hr to km/s! for stationary crew member ..........with eastward still negative -45 km/hr-43 km/hr= -88 km/hr/1.8 sec be sure to convert km/hr to km/s again. note that i used the formula velocity final- velocity initial divided by time. the trick to this problem was all about assigning one direction as positive and the other negative and sticking to that convention with both reference frames. be sure and write on you problem that you chose eastward as the negative direction so there is no confusion when graded. this might be wrong but hope its good.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.