1. Bell Ringer
1. If the velocity of a particle is nonzero, can the particle’s acceleration be zero? Explain
2. If the velocity of a particle is zero, can the particle’s acceleration be zero? Explain
3. If a car is traveling eastward, can its acceleration be westward? Explain
4. If the average velocity of an object is zero in some time interval, what can you say about the displacement of the object during that interval?

2. Practice Problem 1
A car is traveling due east at 25.0 m/s at some instant.
If its constant acceleration is m/s^2 due east, find its velocity after 8.50 s have elapsed.
If its constant acceleration is m/s^2 due west, find its velocity after 8.50 s have elapsed.

3. Practice Problem 2
A car traveling east at 40.0 m/s passes a trooper hiding at the roadside. The driver uniformly reduces his speed to 25.0 m/s in 3.50 s.
What is the magnitude and direction of the car’s acceleration as it slows down?
How far does the car travel in the 3.5 s period?

4. Practice problem 3 (Involving 2 objects)
A car traveling at a constant speed at 24.0 m/s passes a trooper hidden behind a billboard
One second after the speeding car passes the billboard, the tropper sets off in chase with a constant acceleration of 3.00 m/s^2.
How long does it take the trooper to overtake the speeding car?
How fast is the trooper going at that time?

5. Practice Problem 4 (Involving two objects)
A motorist with an expired license tag is traveling at 10.0 m/s down a street
And a policeman, taking another 5.00 s to finish his donut, gives chase at an acceleration of 2.00 m/s^2.
Find
The time required to catch the car
The distance the trooper travels while overtaking the motorist

6. Practice Problem 5 (Involving horizontal motion with two phases)
A typical jetliner lands at a speed of 160 mi/h and decelerates at the rate of (10 mi/h)/s.
If the plane travels at a constant speed of 160 mi/h for 1.0 s after landing before applying the brakes…
…What is the total displacement of the aircraft between touchdown on the runway and coming to rest?

7. Practice Problem 5 (Involving horizontal motion with two phases)
A jet lands at 80.0 m/s, the pilot applying the brakes 2.00 s after landing. Find the acceleration needed to stop the jet within 5.00 x 10^2 m.