Note! In this lab when you measure, round all measurements to the nearest meter!

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2 Distance and Displacement Lab Note! In this lab when you measure, round all measurements to the nearest meter! 1. Place a piece of tape where you will begin your walk outside. This tape marks the origin. 2. Walk 10 steps forward and stop. Using the meter stick, have your partner measure the distance you walked. Write that distance here: (don t forget units!) 3. Now turn 180 degrees and walk 5 steps and stop. Using the meter stick, have your partner measure the distance you walked. Write that distance here: (don t forget units!) 4. Now turn 180 degrees and walk 20 steps and stop. Using the meter stick, have your partner measure the distance you walked. Write that distance here: (don t forget units!) 5. Finally, have your partner measure how far you are from the origin. Write that measurement here: This is your measured displacement. 6. Figure out the distance and calculated displacement you walked. Add all measurements to find the distance: Add all forward measurements and subtract all backwards measurements to find the calculated displacement: Did your measured displacement match your calculated displacement? 7. Find your piece of tape again, and walk 10 steps forward and measure how far you walked. Write it here: (don t forget your units!) 8. Turn 90 left, walk 15 steps and measure how far you walked. Write it here: 9. Turn 90 left, walk 10 steps and measure how far you walked. Write it here: 10. Turn 90 left, walk 20 steps and measure how far you walked. Write it here: 11. Have your partner measure how far you are form the origin. Write it here: This is your measured displacement. 12. Now figure out your distance and write it below. Show your work. Add up the measurements you wrote in numbers 7 through 10. Distance = Now figure out your calculated displacement and write it below. Show your work. Add number 7 + number 8 then subtract number 9 and number 10. Calculated Displacement = Does your calculated displacement match your measured displacement? 13. Find your piece of tape again, and walk 20 steps forward. Measure how far you walked and write it here: 14. Turn 90 right and walk 20 steps. Measure how far you walked and write it here: 15. Have your partner measure how far you are from the origin, your measured displacement, and write it here: (Turn this page over and continue.)

3 16. Now figure out your distance and write it below. Show your work. Add number 14 and 15. Distance = Here s a way to figure out your calculated displacement. You can use Pythagoras Theorem! Add the square of number 13 and the square of number 14. Write it here: Now square the distance you measured in number 15 (your measured displacement). Write it here: The two numbers should be equal or nearly so. If you have a calculator, find the square root of the value you found for the sum of the square of #13 and square of #14. This value is your calculated displacement. Does it match your measured displacement (or nearly so)? 17. Now diagram the last walk and indicate displacement with a vector arrow. Show all your measured distances and displacements on the diagram. 18. Show with the same diagram how you used Pythagoras theorem to find your calculated displacement. Label the square of each leg of your triangle on the diagram. 19. Can you explain why Pythagoras Theorem can be used to find the calculated displacement in your last walk? Hint: you made a 90 degree turn on your walk. 19. Explain why displacement is a vector quantity.

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23 ...Name(s) Speed and the Two-Step Objective: In this lab, you will measure and graph your speed and acceleration as you walk from o another. Step 1: Marking Your Space. You will use the hallway or some other large area to measure a dis string and a meter stick. For our class, we can skip this step because the tiles on the floor are exa Use masking tape to mark a section of tile that equals 20 feet. We will be going into the hallway fo experiment. Do not disturb other classes. Step 2: Speed of a Shuffle Have one person in your group shuffle the length. This means the person s feet should never lea to move you will need to slide your foot in front of the other. This should be a very slow pace. Ano group should time how long it takes (in seconds) to move the 20 feet and record it in the data table. that you can get an average. Step 3: Speed of a Heel-to-Toe Walk This time, you can lift your foot, but must walk by placing one foot exactly at the toe of the other foot with each step. This should also be a fairly slow pace because your steps are tiny. Step 4: Normal Walk For this trial, you can step normally across the length. Try to keep your pace constant. Step 5: Repeat this process by switching to the other person in your group

24 Name of Person Walking: Trial (Person 1) Time to Move 20 ft Shuffle (trial 1) Shuffle (trial 2) Shuffle (trial 3) Average Heel-to-Toe (trial 1) Heel-to-Toe (trial 2) Heel-to-Toe (trial 3) Average Normal Walk (trial 1) Normal Walk (trial 2) Normal Walk (trial 3) Average Name of Person Walking: Trial (Person 1) Time to Move 20 ft Shuffle (trial 1) Shuffle (trial 2) Shuffle (trial 3) Average Heel-to-Toe (trial 1) Heel-to-Toe (trial 2) Heel-to-Toe (trial 3) Average Normal Walk (trial 1) Normal Walk (trial 2) Normal Walk (trial 3) Average Speed (feet/s) Speed (feet/s) ***From this point on, you will be doing the work on you Step 5: Conversions for Fun use the ratio to determin walk (use average) in a minute Now convert your feet per minute to feet per hour (there in an hour) Finally, determine your speed in miles per hour using t 1 mile = 5380 feet. Set up a ratio similar to those above Step 6: Graph your data. Compare the AVERAGE fo walks you and your partner did (shuffle, heel-to-toe, an making a BAR graph. You may want to use different c distinguish between you and your partner.

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30 The moving man Procedure Go to and find The Moving Man simulation under the category of motion. 1. After The Moving Man is open leave the position graph and the velocity graph open but close the acceleration graph by clicking the symbol in the upper righthand corner of the graph. Investigate Moving Man by dragging the dude around with your mouse. This will give you very jumpy data, especially in the acceleration graph why? Now try making the man move using the slider arrows. Use the playback features to look at the graphs. While you make observations, discuss in your group the reasons the graphs look the way they do. 2. Making predictions: on your paper, sketch six of the following graphs. Label them A F. For each of the six scenarios below, in one color, PREDICT what the distance vs. time and velocity vs. time will look like. Don t be afraid to be wrong and don t cheat by looking at Moving Man first! Leave some space for explanations beside or below each graph. A) A man moving from the center of the screen (0 m) to the house (8m) at a slow, steady pace. of the graphs: Explain your reasoning for the appearance

31 B) A man moving from 0 to the house at a faster pace than above. of the graphs: Explain your reasoning for the appearance C) A man standing still at 4 m. of the graphs: Explain your reasoning for the appearance

32 D) A man moving from 0 to the house at a fast pace then moving back to 0 at a slower pace. of the graphs: Explain your reasoning for the appearance 5. Individually write a possible scenario for the following graph. Then compare your scenario with your lab partners to check if it is reasonable. time

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36 Name: Date: Hour: Calculations with Velocity and Acceleration Read and solve each of the following problems. Be sure to show all of your work (given, equation, work, and answer with the proper units) Velocity Equations: 1. What distance is traveled by a police car that moves at a constant speed of 2.5 m/s for 20s? Given: v= d= t= Equation & Work: Answer: 2. What is the speed of a horse that travels 45 m in 2 minutes? (remember to convert minutes to seconds) Given: Equation & Work: v= d= t= Answer: 3. How long would it take for a commercial jet to get from St. Louis to New York, a distance of 1,406 km, if it travels at an average velocity of 156 m/s. (You will also need to do some conversions here to match your units) Given: Work: v= d= t= Equation & Answer:

37 Acceleration Equations: 4. A skier takes off from the top of the ski run and reaches a speed of 24 m/s in 4 seconds. What is the skier s acceleration? Given: Work: vi = vf = t = a = Equation & Answer 5. A child on a skateboard is traveling at a velocity of 8 m/s down a hill. At the bottom of the hill, he slows down and comes to a stop in 4 seconds. Calculate the sled s deceleration (negative acceleration). Given: vi = vf = t = a = Answer Equation & Work: 6. A skydiver jumps out of a plane and as he falls he has an acceleration of 9.8 m/s2. How many seconds will it take to reach a speed of 28.5 m/s? Given: vi = vf = t = a = Equation & Work: Answer

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