Final answer:
The final velocities of the masses can be determined using the laws of conservation of momentum and kinetic energy. If both disks are moving with the same velocity magnitude before the collision, they are likely to move in opposite directions after the collision. Mass A will stop after the collision, while mass B will move with a velocity of 9 m/s in the +x-direction.
Step-by-step explanation:
The final velocities of the masses after the collision depends on the laws of conservation of momentum and kinetic energy. If both disks are moving with the same velocity magnitude before the collision, they are likely to move in opposite directions after the collision. The final velocities of the masses can be determined using the equations:
- mAvAf + mBvBf = mAvAi + mBvBi
- 0.5kg \times vAf + 0.5kg \times vBf = 0.5kg \times (-9m/s) + 0.5kg \times (0m/s)
- 0.5kg \times vAf + 0.5kg \times vBf = -4.5kg.m/s
Since mass A will stop after the collision, the final velocity of mass B can be determined as:
- vBf = -\frac{0.5kg \times vAf}{0.5kg} = -(-9m/s) = 9m/s
Therefore, the correct answer is b. Mass A will stop; mass B will move 9 m/s in the +x-direction.