A car traveling at 120 strikes a tree. The front end of the car compresses and the driver comes to rest after traveling 0.90 .

What was the magnitude of the average acceleration of the driver during the collision? Express the answer in terms of "'s," where 1.00 = 9.80 .

1 answer

Lets get acceleration.
Vf^2 = Vi^2 + 2a*d
Vf = Final velocity
Vi = Initial veloctiy
a = acceleration
d = distance traveled

0 = (120)^2 + 2a(0.90)
a = -8000

Ava = (Vf - Vi/(Tf - Ti)
First must find time.
Ava = average acceleration
Vf = Vi + a*T

Tf = final time, Ti = initial time

0 = 120 -8000*T
T = 0.015

Ava = (0 - 120)/(0 - 0.015)
Ava = 8000

8000 * 9.80
Magnitude of Ava = 78,400 or 8000s