System Open or Closed#

Two buss collide on a track. Bus A comes up behind bus B and runs into it. Bus A has mass of 139 kg, bus B has mass of 323 kg. The following graph shows the velocity of each bus as a function of time.

A velocity versus time graph where {{ params.vars.vehicle }} A has an initial velocity of 8 meters per second and {{ params.vars.vehicle }} B has an initial velocity of 1 meter per second. The two {{ params.vars.vehicle }}s collide at around 4 seconds. The velocity of {{ params.vars.vehicle }} A decreases to 2 meters per second and the velocity of {{ params.vars.vehicle }} B increases to 5 meters per second.

Question Text#

Is the system isolated? Why or why not?

Answer Section#

  • Yes, because the two carts are on a track with no friction.

  • Yes, because their change in velocities are the same.

  • No, because the total momentum is nonzero.

  • No, because the momentum is not conserved


Problem is licensed under the CC-BY-NC-SA 4.0 license.
The Creative Commons 4.0 license requiring attribution-BY, non-commercial-NC, and share-alike-SA license.