The distance-time graphs below represent the motion of a car. Match the descriptions with the graphs. Explain your answers.

Transcription

1 Motion Graphs 6 The distance-time graphs below represent the motion of a car. Match the descriptions with the graphs. Explain your answers. Descriptions: 1. The car is stopped. 2. The car is traveling at a constant speed. 3. The speed of the car is decreasing. 4. The car is coming back. Graph A matches description because. Graph B matches description because. Graph C matches description because. Graph D matches description because. M. Poarch

2 Model Problems An Airplane is descending to land at the airport. During its descent it had to fly in circles until the landing was cleared of other planes. Explain what is occurring during each of the segments. 1) 2) John left his home and walked 3 blocks to his school, as shown in the accompanying graph. What is one possible interpretation of the section of the graph from point B to point C? (1) John arrived at school and stayed throughout the day. (2) John waited before crossing a busy street. (3) John returned home to get his mathematics homework. (4) John reached the top of a hill and began walking on level ground.

3 Practice Problems 3) Jen left her house and drove to school in the morning, as shown in the accompanying graph. On her drive to school she realized that she forgot her bookbag and had to return home before driving back to school for a 3 hour class. Explain what is happening during each part of the graph below AB BC CD DF 4) The accompanying graph shows Marie s distance from home (A) to work (F) at various times during her drive. a b Marie left her briefcase at home and had to return to get it. State which point represents when she turned back around to go home and explain how you arrived at that conclusion. Marie also had to wait at the railroad tracks for a train to pass. How long did she wait?

4 Motion Graphs 10 Questions: ( Some questions adapted from Look at the graph above. It shows how three runners ran a 100-meter race. Which runner won the race? Explain your answer. Which runner stopped for a rest? Explain your answer. How long was the stop? Explain your answer. How long did Bob take to complete the race? Explain your answer. Calculate Albert s average speed. (Figure the distance and the time first!) M. Poarch

5 5)A bug travels up a tree, from the ground, over a 30-second interval. It travels fast at first and then slows down. It stops for 10 seconds, then proceeds slowly, speeding up as it goes. Which sketch best illustrates the bug s distance (d) from the ground over the 30-second interval (t)?

6 Open Interpretation Make up a narrative that could explain the distance vs time graphs below. Explain what is happening for each segment 6) 7) Once I have checked these problems do the activity at Show me the distance vs time graph that you create on that web page Then with a partner complete the interactive activity here :

7 DISTANCE, TIME, SPEED PRACTICE PROBLEMS YOU MUST SHOW YOUR WORK. You can use a calculator but you must show all of the steps involved in doing the problem. SPEED 1. If a car travels 400m in 20 seconds how fast is it going? 2. If you move 50 meters in 10 seconds, what is your speed? 3. You arrive in my class 45 seconds after leaving math which is 90 meters away. How fast did you travel? 4. A plane travels 395,000 meters in 9000 seconds. What was its speed? 5. It takes Serina 0.25 hours to drive to school. Her route is 16 km long. What is Serina s average speed on her drive to school? TIME 6. How much time will it take for a bug to travel 5 meters across the floor if it is traveling at 1 m/s? 7. You need to get to class, 200 meters away, and you can only walk in the hallways at about 1.5 m/s. (if you run any faster, you ll be caught for running). How much time will it take to get to your class? 8. In a competition, an athlete threw a flying disk 139 meters through the air. While in flight, the disk traveled at an average speed of 13.0 m/s. How long did the disk remain in the air?

8 DISTANCE 9. How far can you get away from your little brother with the squirt gun filled with paint if you can travel at 3 m/s and you have 15s before he sees you? 10. How far can your little brother get if he can travel at 2.5 m/s and in 5 seconds you will discover that his squirt gun has run out of paint? 11. If you shout into the Grand Canyon, your voice travels at the speed of sound (340 m/s) to the bottom of the canyon and back, and you hear an echo. How deep is the Grand Canyon at a spot where you can hear your echo 5.2 seconds after you shout? CHALLENGE PROBLEM Bill and Amy want to ride their bikes from their neighborhood to school which is 14.4 kilometers away. It takes Amy 40 minutes to arrive at school. Bill arrives 20 minutes after Amy. How much faster (in meters/second) is Amy s average speed for the entire trip? Be sure to show all necessary metric conversions!!