A cameraman on a pickup truck is traveling westward at 17 km/h while he videotap

Question

A cameraman on a pickup truck is traveling westward at 17 km/h while he videotapes a cheetah that is moving westward 40 km/h faster than the truck. Suddenly, the cheetah stops, turns, and then run at 45 km/h eastward, as measured by a suddenly nervous crew member who stands alongside the cheetah's path. The change in the animal's velocity takes 2.3 s. What are the (a) magnitude and (b) direction of the animal’s acceleration according to the cameraman and the (c) magnitude and (d) direction according to the nervous crew member?

Explanation / Answer

for cameraman,

initial velocity of chetaah,

vi = +40 km/h (taking westward as +ve direction)

final velocity, vf = - 45 - 17 = - 62 km/h

(A) a = (vf - vi)/t

a = (- 62 - 40)(1000/3600 m/s) / 2.3s

a = - 12.3 m/s^2

magnitude = 12.3 m/s^2

(B) direction -> to the east .

(c) as seen by crewman,

vi = 40 + 17 = 57 km/h

vf = -45 km/h

a = (-45-57)(1000/3600)/2.3 = -12.3 m/s^2

magnitude = 12.3 m/s^2

(D) direction = eastward

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.