Name: Partner(s): Date:

Activity 8-1E/F / TOY CAR TIME TRIALS /20 / Science 10
In order to analyze motion, you need both position and time data. A recording timer is a device that vibrates at a uniform rate. Most recording timers have a frequency of 60 Hz. This means that if you pull a ticker tape (a narrow paper strip) through the recording timer it will create 60 dots in once second. You can use the ticker tape to analyze the motion of an object. In this activity, you will use a recoding timer to analyze the motion of a toy car.

QUESTION:

How closely does a toy car’s motion approximate uniform motion?

**Please note that the Toy Cars are fragile and should not be used inappropriately. If you break it you will be assessed to replace the car.

PROCEDURE:

Part 1: Collecting Data

  1. Set up your recording timer so that it is stable. Thread the ticker tape through the recording timer shiny side up.
  2. On a flat surface such as the floor or a lab bench, attach the ticker tape to the back of the car using masking tape.
  3. Once the car has travelled about 10cm, turn on the recording timer. Allow the car to pull all of the tape through the timer (if you are working on a lab bench do not let the car go over the edge!!).
  4. On the back of the ticker tape label it TRIAL 1.
  5. Get a flat board from the front desk. Using an upside down stool, make the board into a ramp.
  6. Set up your recording timer and thread a new piece of a ticker tape through and attach it to the car using masking tape.
  7. Set up the toy car so that it will go up the ramp. MAKE SURE THAT THE CAR IS STABLE ON THE RAMP AND THAT IT WILL TRAVEL UP WITHOUT FALLING OFF! Take a practice run (without ticker tape) before if need be!
  8. Once you are sure the car will travel without falling – turn the car on. Make sure to have spotters just in case the car falls off the edge.
  1. Once the car has travelled up about 10cm turn on a recording device and let the ticker tape pull through until the car reaches the end of the ramp.
  2. On the back of the ticker tape label it TRIAL 2.
  3. Next your car will travel down the ramp. Get a final piece of ticker tape and attach it to the car.
  4. Being careful that you car will not fall off the ramp, turn the car on.
  5. Let the car travel 10cm and turn on the recording device. Stop the car before it hits the bottom of the ramp.
  6. On the back of the last ticker tape label it TRIAL 3.

Part 2: Marking the Ticker Tape

  1. Draw a line through the first dot on the ticket tape and label it t=0.0s.
  2. From the t=0.0s line, count six dots and draw a line through the sixth dot. Since the recording timer produces 60 dots per second, these six dots would represent a time interval of 0.1s. Label the line you just drew t=0.1s.
  3. Count another six dots from the t=0.1s line and mark with dot t=0.2s.
  4. Continue to mark your ticker tape with way until you mark up to 1.0s.
  5. Do this with all three ticker tapes.
  6. Measure the displacement between each of the time intervals for each ticker tape and record the measurements into the tables below.

TRIAL 1 TRIAL 2 TRIAL 3

Time Interval (s) / Displacement
(cm [forward]) / Time Interval (s) / Displacement
(cm [forward]) / Time Interval (s) / Displacement
(cm [forward])
0.0-0.1 / 0.0-0.1 / 0.0-0.1
0.1-0.2 / 0.1-0.2 / 0.1-0.2
0.2-0.3 / 0.2-0.3 / 0.2-0.3
0.3-0.4 / 0.3-0.4 / 0.3-0.4
0.4-0.5 / 0.4-0.5 / 0.4-0.5
0.5-0.6 / 0.5-0.6 / 0.5-0.6
0.6-0.7 / 0.6-0.7 / 0.6-0.7
0.7-0.8 / 0.7-0.8 / 0.7-0.8
0.8-0.9 / 0.8-0.9 / 0.8-0.9
0.9-1.0 / 0.9-1.0 / 0.9-1.0

Using the data from your data tables graph all 3 car trials onto the grid below as a Position-Time Graph. Be sure to label the axes and include units. Use 3 different colours to plot a ‘best-fit’ line for each.

Answer the questions below regarding your graph:

  1. How did each of the Trails lines differ? What does the slope of each line tell us?

______

  1. Was the car moving in uniform motion in any of the trails? Explain why or why not.

______

  1. Explain why the slopes of each trial are different.

______

Use the graph to the left to answer the next 3 questions.

  1. For each of the time intervals to the left, describe the motion of the object. Be sure to include the direction when necessary.
  1. 0s-4s
  1. 4s-8s
  1. 8s-10s
  1. Calculate the displacement for each of the following time intervals.
  1. 0s-4s
  1. 4s-8s
  1. 8s-10s
  1. 0s-10s
  1. What total distance did the object travel in the time interval 0s - 10s?