- #1
FancyNut
- 113
- 0
A 2.0 kg wood block is launched up a wooden ramp that is inclined at a angle. The block's initial speed is 10 m/s . The coefficient of kinetic friction of wood on wood is .200.
So that's the intro... The first question is to get the hight it reachers on the incline and I got that right = 3.79 meters. During solving the first part I got delta x and it's = 1.89 meters.
it's the second part I don't know and it actually looks like the easier part.
What speed does it have when it slides back down to its starting point?
I anaylized the block from its position on top again with friction being positive (because its direction is right) and calculated the new acceleration which turned out to be -3.2 m/s^2.
Just to be sure this is it:
[tex]a_x = (u_k mgcos(30) - mgsin(30) )/m[/tex]
of course I got mg out and m canceled with the bottom and the the final expression looked different..
I know the initial velocity is zero, so the final one (where it reaches the part it started on in the introduction) is the square root of 2 times acceleration times delta x... all numbers I have.
The number I got was 3.46 m/s and it turned out to be incorrect. =\
Where did I go wrong here? Thanks for any advice! :)
So that's the intro... The first question is to get the hight it reachers on the incline and I got that right = 3.79 meters. During solving the first part I got delta x and it's = 1.89 meters.
it's the second part I don't know and it actually looks like the easier part.
What speed does it have when it slides back down to its starting point?
I anaylized the block from its position on top again with friction being positive (because its direction is right) and calculated the new acceleration which turned out to be -3.2 m/s^2.
Just to be sure this is it:
[tex]a_x = (u_k mgcos(30) - mgsin(30) )/m[/tex]
of course I got mg out and m canceled with the bottom and the the final expression looked different..
I know the initial velocity is zero, so the final one (where it reaches the part it started on in the introduction) is the square root of 2 times acceleration times delta x... all numbers I have.
The number I got was 3.46 m/s and it turned out to be incorrect. =\
Where did I go wrong here? Thanks for any advice! :)