- #1
Plutonium88
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Yet another question i was unable to finish last semester which still bugs me... D:
A ball drops from (H) with a velocity = 0. with a mass M. It collides with an inclined plane with a mass M1. the ball goes exactly horizontally to the right, the incliend plane goes to the left. Momentum is conserved in the X direction. Energy is conserved. What are the velocities of the plane and the ball after collision? The angle of the inclined plane is 45 degrees.
here is a picture of the question
http://s12.postimage.org/a8lmqwqwd/momentum_conserved_in_the_x.png
My attempt:
So i set the gravitational potential point at 0 where the height is.
ET1 = ET2
EG1 = EK2
mgh=1/2mv2^2
V2= √MGH
This is the velocity before the collision. it is also in the Y direction according to my axis.
so now.. I'm stuck.. because how can i compare a Y momentum with an x compenent which is conserved... what is the relation i don't see it at all...
collision formula: mv2y+0 = mv2y' M1vm1y'
but now I'm left with two unknowns..
so i compare change in EK between... from where it falls to before the collision.
ΔEKball = 1/2 mv2^2 - 0
ΔEKball = 1/2 M1Vm1^2 - 0
but i I'm not sure if this comparison is possible... :(
some advice is required please :(
A ball drops from (H) with a velocity = 0. with a mass M. It collides with an inclined plane with a mass M1. the ball goes exactly horizontally to the right, the incliend plane goes to the left. Momentum is conserved in the X direction. Energy is conserved. What are the velocities of the plane and the ball after collision? The angle of the inclined plane is 45 degrees.
here is a picture of the question
http://s12.postimage.org/a8lmqwqwd/momentum_conserved_in_the_x.png
My attempt:
So i set the gravitational potential point at 0 where the height is.
ET1 = ET2
EG1 = EK2
mgh=1/2mv2^2
V2= √MGH
This is the velocity before the collision. it is also in the Y direction according to my axis.
so now.. I'm stuck.. because how can i compare a Y momentum with an x compenent which is conserved... what is the relation i don't see it at all...
collision formula: mv2y+0 = mv2y' M1vm1y'
but now I'm left with two unknowns..
so i compare change in EK between... from where it falls to before the collision.
ΔEKball = 1/2 mv2^2 - 0
ΔEKball = 1/2 M1Vm1^2 - 0
but i I'm not sure if this comparison is possible... :(
some advice is required please :(