1. 1
By what factor does the kinetic energy of a car change when its speed is tripled?
1) no change at all
2) factor of 3
3) factor of 6
4) factor of 9
5) factor of 12

2. 2
1) 2 v1 = v2
2)  2 v1 = v2
3) 4 v1 = v2
4) v1 = v2
5) 8 v1 = v2
Car #1 has twice the mass of car #2, but they both have the same kinetic energy. How do their speeds compare?

3. 3
A child on a skateboard is moving at a speed of 2 m/s. After a force acts on the child, her speed is 3 m/s. What can you say about the work done by the external force on the child?
1) positive work was done
2) negative work was done
3) zero work was done

4. 4
If a car traveling 60 km/hr can brake to a stop within 20 m, what is its stopping distance if it is traveling 120 km/hr? Assume that the braking force is the same in both cases.
1) 20 m
2) 30 m
3) 40 m
4) 60 m
5) 80 m

5. 5
A car starts from rest and accelerates to 30 mph. Later, it gets on a highway and accelerates to 60 mph. Which takes more energy, the 030 mph, or the 3060 mph?
1) 0  30 mph
2) 30  60 mph
3) both the same

6. 6
1) 2 W0
2) 3 W0
3) 6 W0
4) 8 W0
5) 9 W0
The work W0 accelerates a car from 0 to 50 km/hr. How much work is needed to accelerate the car from 50 km/hr to 150 km/hr?

7. 7
Two blocks of mass m1 and m2 (m1 > m2) slide on a frictionless floor and have the same kinetic energy when they hit a long rough stretch (m > 0), which slows them down to a stop. Which one goes farther?
1) m1
2) m2
3) they will go the same distance m1 m2