A Retired Lady Uses the Fremont Track Each Day to Get Her Exercise

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Practice Problems for Kinematics Test

Problems using average velocity:

1. A retired lady uses the Fremont track each day to get her exercise. She runs 2 laps in lane one, and then walks two laps in lane one. She runs at 4 m/s, and walks at 2 m/s. What is her average speed (velocity) for the entire 1600 m?

2. A retired lady uses the Fremont track each day to get her exercise. She runs 2 laps in lane one, and then walks two laps in lane one. She runs at 4 m/s, and wishes to average 3 m/s for the entire exercise. How fast must she walk to reach her goal?

Problems using simultaneous equations:

3. Two tykes on trikes are racing. The red tricycle starts 30 m in front of the blue tricycle. The red tricycle has a constant velocity of 2 m/s. The blue tricycle has a constant velocity of 5 m/s. When, and where, does the blue trike catch the red trike?

4. Two tykes on trikes are racing. Both start at the same time and at the same place. The red tricycle has a constant velocity of 10 m/s. The blue tricycle has a constant acceleration

of 2 m/s/s. When, and where, does the blue trike catch the red trike? At what time do both bikes have the same velocity? How far apart are both bikes at the instant they have the same velocity? Make a position vs time graph, and a velocity vs. time graph that shows the motion of both bikes. Use the graphs to determine the instant that the trikes are passing, and the instant the two trikes have the same velocity.

Quadratic Problems:

5. A car is approaching an intersection 14 m away with a velocity of 16 m/s. The brakes are applied when the light turns yellow causing an acceleration of –8.00 m/s/s. If the light remains yellow for 3 seconds, does the driver avoid being in the intersection when the light turns red?

6. A softball is thrown into the air with an initial velocity of 39.2 m/s. Determine it’s height at the apex, and the clock reading for the instant it reaches the apex.

7. A softball is thrown into the air with an initial velocity of 39.2 m/s. What is the clock reading when the softball returns to the ground?

8. A softball is thrown into the air with an initial velocity of 39.2 m/s. What is the clock reading when the softball is 58.8 m above the ground?

9. A softball is thrown straight up from the edge of a cliff with an initial velocity

of 39.2 m/s. On the return path, it passes the edge of the cliff and continues downward. At what instant is the softball 98 m below the edge of the cliff? (d = -98 m)

10. A fan cart is pushed with a velocity of 4 m/s on a long track. The operating fan gives the cart an acceleration of – 2 m/s/s. What is the clock reading and position of the cart when it stops to turn around?

11. A fan cart is pushed with a velocity of 4 m/s on a long track. The operating fan gives the cart an acceleration of – 2 m/s/s. At what instant does the cart pass the 3 m position?