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gregorio13
Oct 1, 2008, 05:29 PM
In coming to a stop, a car leaves skid marks 79m long on the highway. Assuming a deceleration of 6.2m/s2 , estimate the speed of the car just before braking... I don't need th answer I need the givens

Credendovidis
Oct 1, 2008, 06:25 PM
In coming to a stop, a car leaves skid marks 79m long on the highway. Assuming a deceleration of 6.2m/s2 , estimate the speed of the car just before braking... i dont need th answer i need the givens

This link will provide you with a good explanation how to approach this question ! (LINK) (http://www.glenbrook.k12.il.us/GBSSCI/PHYS/CLASS/1DKin/U1L1d.html)

Also see chapter acceleration !

Success with your homework !

:)

excon
Oct 1, 2008, 06:27 PM
Hello g:

Four.

excon

Unknown008
Oct 5, 2008, 09:26 PM
I would use a sketch graph. Using vectors, the vector for the decceleration will be

(1 )
(6.2)

So, distance covered in 1 s= (1 x 6.2)/2 = 3.1m
For 79m, then (79/3.1)=25.48s = 25.5s

Therefore, initial speed = 6.2 x 25.5 = 158 m/s