You are a traffic accident investigator. You have arrived at the scene of an accident. Two trucks of equal mass (3,000 kg each) were involved in a rear-end accident at a stop sign. Here is what you know:

• Truck 1 started from rest at the top of a 22-meter hill and coasted toward the intersection.
• Truck 2 was on a flat stretch of road at the bottom of the hill directly in front of Truck 1.
• At the bottom of the hill, Truck 1 was going 20 m/s; Truck 2 was going 35 m/s.
• There were no skid marks left by Truck 2. The collision occurred at the stop sign where Truck 2 had stopped.
• After the collision, both trucks moved together in the same direction at 10 m/s before slowly rolling to a stop.

You must now push Truck 2, using 1,000 N of force, 8 meters off to the side of the road so no one else gets hurt.

8. How much energy did Truck 1 lose in the collision? (3 points)

9. How much energy did Truck 2 gain in the collision? 10. Which of the two laws covered in this unit - Law of Conservation of Momentum or Law of Conservation of Energy - is obeyed in this problem? Explain your reasoning.