- #1
mjmontgo
- 10
- 0
Homework Statement
In deep space a 7.0 kg rubber ball moving along the x-axis with a speed of 20 m/s collides ELASTICALLY with another ball of mass = 25 kg. After the collision the 7.0kg rubber ball's velocity is directed in the positive y axis. Find the final speed of the 7 kg ball, as well as the VELOCITY of the 25 kg ball (speed and direction)
Homework Equations
m1v1= m1v1f+m2v2f
1/2m1v12= 1/2m1v1f2 +1/2m2v2f2
The Attempt at a Solution
so i know that because the smaller mass is afterwards directed in the positive y direction, that all of its x momentum is transferred to the bigger mass. I've found a velocity for the x component of the bigger mass, however I am stucking finding the y component, which in turn would give me the over all final velocity, which i can use to calculate the angle as well as the final speed of the smaller mass. Would be greatly appreciated if someone could point out the extra equation I am missing. Basically what i have so far boils down to these equations:
m1v1x= m2v2finalx and i work out the x component of the larger mass to be 140/25 m/s
the other equation i have is for the y direction and that is :
-m2v2fy= m1v1fy
i know i somhow need to use the energy conservation formula but I am just not seeing it.
Thanks a lot in advance for you help and time guys.