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1. The problem statement, all variables and given/known data

In the figure below, a small block is sent through point A with a speed of 8.1 m/s. Its path is without friction until it reaches the section of length L = 12 m, where the coefficient of kinetic friction is 0.70. The indicated heights are h1 = 8.0 m and h2 = 1.1 m.

(Image Attached)

(a) What is the speed of the block at point B?

15 m/s

(b) What is the speed of the block at point C?

14.1 m/s

(c) Does the block reach point D?

---Select--- yes no

If so, what is its speed there and if not, how far through the section of friction does it travel?

in units of m/s

2. Relevant equations

Kinematics equations

Mu*N= Fkinetic

3. The attempt at a solution

Now, I've already finished a, b, c, I just need help with d. I first determined that all I had to do was set up a kinematics graph and use point C as my starting point. So, my inital velocity would be 14.1, my acceleration (which I got from using the second equation above, the normal force is equal to the weight for mg) is -6.86, and my delta-x is 12.

I realize that the picture does not depict L to be 12 exactly, but I see no other way to do this. Then, using the Vf^2=Vo^2 +2ax equation I solved for Vf. My answer was 5.84 m/s, however, this is incorrect. Could someone lead me to the right direction???

Thanks in advance!

~Phoenix

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# Homework Help: Work, Velocity, Friction, and Potential Engery with a sliding block

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