A 1590 kg car moving south at 14.3 m/s collides with a 2650kh car moving north.
The cars stick together and move as a unit after the collision at a velocity of 5.71 m/s to the north.
Find the velocity of the 2650 kg car before the collision. Answer in units of m/s.
The cars stick together and move as a unit after the collision at a velocity of 5.71 m/s to the north.
Find the velocity of the 2650 kg car before the collision. Answer in units of m/s.
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When "stuff sticks" as in the cars stick together, then the easy laws of momentum come into play.
MV + MV = MV (and M= mass an V = velocity)
first car (1590 kg) moves with speed -14.3 m/s. The number is negative because it is moving south. You could have south designated as positive but I like to have south and west as negative because that's how it is on the traditional coordinate system.
Second car is 2650 kg with unknown ( but positive, because it is traveling north) speed.
Mass X Velotcity + Mass X Velocity = (New) Mass + Velocity
(1590 kg)(-14.3 m/s) + (2650 kg)(unknown) = (1590 kg + 2640 kg)(5.71 m/s)
Solve for "unknown" and you get the velocity of 2650 kg car. Make sure to note that the unknown will have a positive value because the positive velocity of the heavier car "overpowers" the car moving south.
MV + MV = MV (and M= mass an V = velocity)
first car (1590 kg) moves with speed -14.3 m/s. The number is negative because it is moving south. You could have south designated as positive but I like to have south and west as negative because that's how it is on the traditional coordinate system.
Second car is 2650 kg with unknown ( but positive, because it is traveling north) speed.
Mass X Velotcity + Mass X Velocity = (New) Mass + Velocity
(1590 kg)(-14.3 m/s) + (2650 kg)(unknown) = (1590 kg + 2640 kg)(5.71 m/s)
Solve for "unknown" and you get the velocity of 2650 kg car. Make sure to note that the unknown will have a positive value because the positive velocity of the heavier car "overpowers" the car moving south.
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use law of conservation of momentum.