The skid marks at an auto crash site are 33.3 m long. A braking car on dry pavement has a constant acceleration of -6.0 m/s^2. The driver of the colliding car claims that he was going 36 km/h prior to the crash. Which of the following statements is true?

A. The driver was telling the truth because his speed was 36 km/h.

B. The driver was lying because he was traveling at 72 m/s.

C. The driver was lying because he was traveling at 20 km/h.

D. The driver was lying because he was traveling at least 72 km/h.

How does this one work? @perl :)

Question

The skid marks at an auto crash site are 33.3 m long. A braking car on dry pavement has a constant acceleration of -6.0 m/s^2. The driver of the colliding car claims that he was going 36 km/h prior to the crash. Which of the following statements is true?

A.   The driver was telling the truth because his speed was 36 km/h.

B.  The driver was lying because he was traveling at 72 m/s.

C.  The driver was lying because he was traveling at 20 km/h.

D.  The driver was lying because he was traveling at least 72 km/h.

How does this one work? @perl :)

eyust707 · Answer

attachment

perl · Answer

iheartmath :DDDD

eyust707 · Answer

vf = 0
xf - xo = 33.3
a = -6

eyust707 · Answer

use the last one to solve for vo (initial velocity)

anonymous · Answer

haha @perl food is better though!!

and okay @eyust707  :)

perl · Answer

we know that total distance delta x = 33

anonymous · Answer

so 2(-6) * 33.3 = -12*33.3 = -399.6 ? :/

perl · Answer

lets write down the 4 kinematic equations, that will help

anonymous · Answer

are they the equations that @eyust707 attached in the beginning right?

perl · Answer

oh thats it

eyust707 · Answer

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