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## Homework Statement

here is a picture of the problems im having trouble with:

http://oi55.tinypic.com/2llca50.jpg

or if that doesn't work: http://tinypic.com/view.php?pic=2llca50&s=7

## Homework Equations

for question 1:

part 1: p1 + p2 = p`1 + p`2 and Distance=Time*Speed

part 2: W(f) = F(f) x d, where F(f) is the Frictional force and d is the distance moved, and F(f) = μN, where μ is the coefficient of friction (i think)

part 3: i don't understand how there is a height acheived, other than falling 5m down the ramp

for question 2:

part 1, 2 and 3: Ke=1/2mv^2 AND m1v1+m2v2 = m1'v1'+m2'v2'

## The Attempt at a Solution

question 1:

part 1: im really not sure how to figure in friction to this part, all i really know is mgh plays a part. but to what extent, im not sure. this is my biggest problem.

part 2: since i don't know the distance moved, i can't find out the work done by friction

part 3: -5m is the only height achieved that i could see as plausible

question 2:

part 1: 9.6 + 0 = 3.2v+2.0v

v = 9.6/3.2/2.0/2 = .75m/s

Ke = 1/2 (3.2+2)(.75)^2 = 1.46J

part 2: v = .75m/s+(9.8m/s*.2857s[calculated using an online calculator]) = 3.54m/s

Ke = 1/2 (5.2)(3.54)^2 = 32.5j

part 3: theyre different because the connected boxes and gained velocity due to gravity during a freefall, which caused a rise in kinetic energy

i'm fairly clueless as to whether i got any of that right, and you can see i need a strong push in the right direction on the first one.

i really appreciate your help

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