Cuesta College, San Luis Obispo, CA
Cf. Giambattista/Richardson/Richardson, Physics, 2/e, Problem 6.17
Motor Trend Channel
youtu.be/ydykiWKW6fE
A 2011 Ford Mustang GT Premium (mass 1,640 kg) takes 10.3 s to accelerate from rest to 45.0 m/s on a horizontal track[*]. What is the final kinetic energy of this car?
(A) 7.38×104 J.
(B) 7.23×105 J.
(C) 7.60×105 J.
(D) 1.66×106 J.
[*] motortrend.com/roadtests/coupes/112_1003_2011_ford_mustang_gt_premium_test/viewall.html.
Correct answer (highlight to unhide): (D)
The final (translational) kinetic energy of the car is given by:
KEtr,f = (1/2)·m·(vf)2,
KEtr,f = (1/2)·(1,640 kg)·(45.0 m/s)2 = 1,660,500 J,
or to three significant figures, 1.66×106 J.
(Response (A) is m·vf, response (B) is m·g·vf, response (C) is m·vf·t.)
Sections 70854, 70855
Exam code: quiz04iMpL
(A) : 2 students
(B) : 7 students
(C) : 4 students
(D) : 38 students
Success level: 75%
Discrimination index (Aubrecht & Aubrecht, 1983): 0.64
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