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- shm 350g initial extension tension weight model.mov

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Document Brief: Title: "Tracker SHM 350g Initial Extension Tension Weight Model"

This document outlines the use of Tracker software to analyze the simple harmonic motion (SHM) of a 350g weight with an initial extension, focusing on tension dynamics. The session explores modeling SHM, visualizing data, and understanding key physical principles.

Study Guide:

Objective:

• Use Tracker to investigate SHM in a 350g weight with an initial extension.

• Understand how initial extension affects oscillatory motion and tension.

Key Concepts:

1. Simple Harmonic Motion (SHM):

   • Periodic motion driven by a restoring force proportional to displacement.

   • Energy exchanges between potential and kinetic energy.

2. Initial Extension Impact:

   • The effect of stretching the string before release.

   • Relationship between extension and oscillation amplitude.

3. Tracker Analysis:

   • Recording and calibrating oscillatory motion.

   • Generating graphs for position, velocity, and acceleration over time.

Steps for Analysis:

1. Setup:

   • Attach a 350g weight to a tensioned string with a measurable initial extension.

   • Record the oscillation using a high-quality video setup.

2. Import Video to Tracker:

   • Calibrate axes and define the scale using a known reference length.

   • Mark key positions of the oscillation cycle.

3. Analyze Motion:

   • Observe sinusoidal patterns in position-time graphs.

   • Determine amplitude, period, and frequency.

   • Compare experimental values with theoretical predictions.

4. Investigate Effects of Initial Extension:

   • Examine how increased extension changes amplitude and period.

   • Relate observations to tension and restoring force.

Questions to Consider:

1. How does initial extension affect amplitude?

   • Answer: Greater initial extension increases the amplitude of oscillation.

2. What does the velocity-time graph indicate about SHM?

   • Answer: It shows sinusoidal motion, with maximum velocity occurring at equilibrium.

3. How can you calculate tension from Tracker data?

   • Answer: Use mass and acceleration (from the acceleration-time graph) to estimate the net force.

4. What is the significance of energy conservation in SHM?

   • Answer: Energy alternates between potential (elastic) and kinetic forms while total energy remains constant (ignoring damping).

5. What experimental factors may influence results?

   • Answer: Calibration errors, air resistance, and string elasticity variations.

Worksheet

• shmTrackerinstructionSHM17.docx

FAQ:

1. How is initial extension measured in Tracker?

   • By calibrating the system and marking the stretched length before oscillation begins.

2. Can Tracker differentiate small variations in SHM?

   • Yes, with high-resolution video and precise calibration.

3. What is the ideal frame rate for recording SHM?

   • A frame rate high enough to capture multiple points per cycle, typically 120 fps or higher.

4. Does initial extension affect frequency?

   • Only if it changes the effective spring constant or tension.

5. What advanced studies can be done using this model?

   • Investigate damping effects or forced oscillations in extended systems.

Next Steps: Participants should explore how varying initial extensions influence SHM properties, using Tracker to analyze and compare their data. Additional studies may include adding damping or external forcing to the system.