**Practice Problems: Motion Studies**

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1. (easy) A woman walks in a straight line for 40 minutes at an average speed of 1.25 m/s. How far does she travel in this time?

2. (moderate) A car is traveling along a road. It moves according to the following equation:

x = 2.0t^{2} + 0.25t^{3} (x is in meters and t is in seconds)

a) What is the average velocity of the car between 0.0 and 2.0 seconds?

b) What is the average velocity between 2.0 and 4.0 seconds?

3. (moderate) Based upon the following data determine if the average acceleration of the object between 2.0 and 4.0 seconds has a bigger or smaller magnitude than the average acceleration between 4.0 and 6.0 seconds:

velocity at 2.0 seconds is 0.8 m/s

velocity at 4.0 seconds is 1.2 m/s

velocity at 6.0 seconds is 0.6 m/s

4. (moderate) Watch the video below and have a stopwatch available. Cart 1 is shown in the video. Cart 2 (not shown in video) travels 0.2 m in 4.96 seconds. If cart 1 started its motion in Pittsburgh and ended in New York City (370 miles away), how many days ahead of cart 2 would it arrive? Note that the video shows the motion of cart 1 twice. You may need to watch the video several times to make accurate measurements. The red cm markings on the track are 10 cm apart.

5. (easy) Interstate 70 is a highway that runs through the heartland of the United States. If traveler A drove 100 miles along Interstate 70 at 65 mph and traveler B drove the same distance at 55 mph, how much earlier would traveler A arrive?

6. (easy) In a well-formed paragraph, using the concepts described in the presentation, explain why the following statement must be incorrect: "The displacement of an object during an experiment was zero, but the average velocity was not zero." Additionally, how could you change the statement (replace one word with a different word) that would allow it to be true?

7. (OPTIONAL hard) A car is moving along the x-axis of a coordinate system accoring to the following equation:

x = 20 + 5t^{2} (x is in meters and t is in seconds)

a) Find the displacement of the car between the first and second second.

b) Find the average speed during the first and second second.

c) Find the instantaneous velocity at t = 1 second.

8. (OPTIONAL hard) A student jogs from home to the store. She runs at 1 m/s for 1/3 of the time and 1.5 m/s for the remaining time. On her way back home she runs at 1 m/s for half the distance and at 1.5 m/s for the rest of the trip. Find her average speed for the round trip.

**PA Homeschooler Students: Prior to moving to the next assignment in the workflow, you must work through the following scenarios in the AP Physics 1 Student Workbook. If you have mastered the concepts, you should find that the questions in the scenarios can be easily answered. If not, please take advantage of the additional practice found in the companion text.**

Click here to download Student Workbook.

Scenarios 1A and 1C