Physics Labs with Computer Interfaces

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Physics Labs with Computer Interfaces

• Dr. Jing Gao
• Chemistry and Physics Department
• Kean University
• April 12, 2003

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Introduction

• In our physics lab, student use Pascos
• motion sensor to measure their own position, and
  velocity with respect to the sensor
• DataStudio to curve fit their motion live to a
  plot given on the computer display.
• Uniqueness students are the objects being
• measured through direct involvement, they have
  a
• better understanding of the physics.

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Equipments

• Hardware Science workshop interface 750
• (Motion Sensor II)
• Software DataStudio
  

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Motion Sensor II

• Ultrasound pulses are sent out and their echoes
  reflected from an object are detected
• measuring range 0.15mltxlt8m
• Changing in position of an object is measured
  many times each second.
• Trigger rate 5Hzltflt120 Hz
• Use the feedback from the cursor to locate the
  best starting position
• Delay time t3s

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Understand Motion 1 Position and Time
To Interface
Motion Sensor
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Understand Motion 1 xt

• Study the given plot to determine
• How close should you be to the Sensor at start?
• How far away should you move?
• How long should your motion last?
• Data recording
• Find best starting point through cursor feedback.
• Match your motion to the plot already there.
• Repeat several runs to improve the match.

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Position as a function of time

• Given Plot

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Motion descriptions xt

• Starting at 1m from the sensor,
• first 2s no motion,
• with 1m/s speed away from sensor 3s,
• no motion for another 2s,
• with 4m/s speed towards sensor for 1s.

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Position as a function of time

• Matching Plots

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Understand Motion 2 Velocity and Time
To Interface
Motion Sensor
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Understand Motion 2 vt

• Study the given plot to determine
• The direction to go at the beginning
• The maximum speed must achieve
• The Duration of the motion.
• Data Recording
• Challenge Match your motion to the plot
• The vt is more erratic than xt plot.

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Velocity as a function of time

• Given Plot

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Motion descriptions vt

• moving with 1m/s speed for first 20s
• speed increasing constantly to 4m/s during
  20-50s,
• moving with const. speed 4m/s for 20s,
• speed decreasing constantly to zero for the last
  10s

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Velocity as a function of time

• Matching Plots

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Outcome and discussion

• Students are attracted to the technology very
  involved and eager to be challenged.
• They learn while doing it gaining better
  understanding of properties of a motion
• Improve their data analysis computer
  application skills

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Conclusion

• DataStudio computer interface labs provide
  students with a powerful tool in describing and
  analyzing motion of an object graphically.
• Numerous applications in all branches of Physics,
  as well as other science areas, including
  Biology, Chemistry, and Earth Environmental
  Science.