- #1
Troubadour
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Homework Statement
If the engine of a car provides an acceleration of 2ms-2 to start it from rest, assuming the mass to be roughly 1000kg, calculate the time after which the car comes to rest if the engine is turned off after 15 seconds and the frictional force is 15N)
Homework Equations
v=u + at
F= m*a
The Attempt at a Solution
v= 0 + (2)(15) = 30ms-1
F= m*a = -15N= 1000 * a
Therefore, acc. caused by friction= (-15)/1000= -0.015
v=u+at, but car comes to rest, so v = 0
0= 30 +(-0.015)(t) = 2000sec
I'm not really sure of the answer as it seems to be quite impractical (:P).
Thanks.
~Troubadour