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Main » Kinematics & Dynamics » Understanding Motion » Online Activities » Lab I.1.1

### Using a Recording Timer I.1.1

Purpose:

To become familiar with a recording timer and be able to interpret the data on a marked recording tape.

Materials:
 » recording tape » recording tape holder » carbon paper disc » recording timer » C-clamp » stopwatch » ruler

Background Info:

Procedure:

1. Plug in the recording timer and clamp it to the bench.
2. Set the recording tape into the holder and place the carbon paper disc on the target with the carbon side up.
3. Measure 1m on the recording tape. Indicate the starting point and the end point.
4. Thread the end of the recording tape through the support on the recording timer, beneath its hammer but over the carbon paper, and then finally through the last support.
5. Activate the recording timer and start the stopwatch when the starting point passes beneath the striker. Stop it when the end point passes beneath the striker.
6. Record the time for the run.

Data & Analysis:

1. How long did it take the tape to pass beneath the striker from the starting point to the end point as indicated on the recording paper?
2. How many dot intervals did you count between the starting point and the end point?
3. Calculate the frequency of the timer.
4. Calculate the period of the timer.
5. Calculate the change in time between the tenth and eleventh dot.
6. Calculate the number of dot intervals for a change in time of 2 s.
7. Determine the number of dots for a change in time of 2 s.
8. Explain in a sentence(s) how you would determine the change in time between the staring point and the dot closest to 0.7 m away.
9. Predict what would happen to the spacing of the dots if the tape was pulled at different speeds. Try It! Do an experiment to test your prediction and record your results in a table. Conclusion:

 Conclusion: Your conclusion should respond to the purpose. In this particular laboratory that might mean a statement like: The recording timer is a useful tool to record and interpret motion.