Homework Help: Dynamics Question (First-Year)

How should I approach this question:

You are driving at a constant velocity of 25 m/s.
You have antiques in the back of your pick-up truck.
You see a giant hole in the road, 55 m ahead of you.
Coefficients of friction for the antiques: μs=0.6 and μk=0.3.

Can you stop without the antiques sliding and being damaged? (Hint: You're not trying to stop in the shortest possible distance.)


All I have found so far was the acceleration if you were to stop right before the giant hole. The value I calculated is a = -5.68 m/s2. I can't figure out what to do with the coefficients of static and kinetic friction, however.

Thank you.

 

Is the following the correct method of completing the question? :

(x-direction)

Fnet= ma
Fnet= -μsmg

→ ma=-μsmg
a=-μsg=-(0.6)(9.8)
a=-5.88 m/s^2

→ v2^2=v1^2+2ad
d=v2^2-v1^2
¨¨¨¨¨2a
d=(0-25^2) / (2)(-5.88)
d=53 m

→ The car stops in time without the antiques breaking since 53 m < 55 m.

 

... .

 

I'm confused because I did not use the coefficient of KINETIC friction in my answer, but it was given to me.

 

Oh, that makes sense now.

Thanks.