The discussion revolves around a physics problem involving a collision between a ball and a cube on a frictionless table. The ball, initially at rest, is struck by a moving cube, and participants are tasked with determining the velocities of both objects immediately after the collision.
Multiple interpretations of the collision type are being explored, with some participants suggesting it may be elastic while others argue against it. Guidance has been offered regarding the use of momentum conservation, and some participants have shared their calculations for the velocities.
Participants express confusion about the relationship between impulse and the type of collision, and there is a focus on the implications of the graph related to the force exerted during the collision.
physicsgirl101 said:Part d of the problem says: Determine the kinetic energy dissipated in the collision.
I know kinetic energy was lost, because it was an inelastic collision, but when I do it out I get that no kinetic energy is lost:
before collision:
(1/2)(.5)(26^2)+(1/2)(5)(0) = 169
after collision:
(1/2)(.5)(21.27^2) + (1/2)(5)(4.727^2) = approx. 169
I'm assuming I got this incorrect result because the velocities I used (21.27 and 4.727) are incorrect---because the collision would have to be elastic for them to be correct, and thus it makes sense that in an elastic collision the energy would be conserved... So basically this goes back to my last post----I need to find the correct v1 and v2... Can anybody help? Please!
physicsgirl101 said:Alright... After a lot of work, this is what I got:
immediately after the collision:
speed of ball: 2.4m/s
speed of cube: 2m/s (going to the right---the same direction as the ball*)
I then gathered that 153.6 Joules of kinetic energy was lost in the collision...
How does that all sound? (especially the direction of the ball??)