Procedure

In a Real Laboratory

1. Measure Dimensions

   • Measure the dimensions of the object using a vernier caliper.

2. Tabulate Properties

   • Record the object's mass, size, projected area, and the fluid properties (density and coefficient of drag) in a table.

3. Setup Releasing Mechanism

   • Clamp the releasing mechanism on the stand at the desired height inside the cylinder.
   • Fix a ruler or mark graduations on the cylinder for reference.

4. Prepare Cylinder

   • Ensure all openings are fully closed and airtight.
   • For terminal velocity in fluid:
     Fill the cylinder with the fluid up to the electromagnet level.
   • For free-fall in vacuum:
     Activate the vacuum system until the cylindrical chamber is evacuated.

5. Position Light Gates

   • Clamp light gates at intervals (e.g., 20 cm or less) along the cylinder’s height.
   • Align gates so the falling object passes through each one.

6. Secure the Object

   • Attach the object to the electromagnet.
   • If releasing in liquid, wet the object first to prevent air bubbles from clinging.
   • The release switch should also activate the timer (initially set to zero).

7. Check Connections

   • Ensure light gates, electromagnet, data logger, computer, and power supply are properly connected.

8. Release and Record

   • Press the switch to release the object.
   • Verify the computer system records:
     • Time when the object passes each light gate.
     • Time taken to pass through each gate.

9. Note Values

   • Record all measured times and observations.

10. Plot Graphs

    • Draw velocity–time and drag force–time graphs.

11. Repeat Trials

    • Repeat the experiment multiple times to obtain mean values of measured parameters.

In Simulation

1. Set Parameters

   • Use sliders or input boxes to adjust:
     • Mass of object (m)
     • Size of object (s)
     • Projected area (A)
     • Coefficient of drag (C_d) – only for Tube 2
     • Fluid type – only for Tube 2

2. Select Tube

   • Tube 1: Vacuum (for free-fall acceleration)
   • Tube 2: Fluid (for terminal velocity)

3. Initiate Motion

   • Click the "Release" button to start the object’s motion based on the set parameters.

4. Observe Animation & Graphs

   • Watch the object fall in the animation area.
   • Note the object passing through light gates.
   • Monitor the velocity–time graph and drag force–time graph updating in real time.

5. Record Data

   • Record the time (t) when the object passes each light gate, and the time taken to pass through the gate (t′).
   • Light gate positions:
     0.4 m, 0.6 m, 0.8 m, 1.0 m, 1.2 m, 1.4 m, 1.6 m, and 1.8 m.

6. Automatic Calculation & Plotting

   • Velocity and drag force are calculated automatically.
   • Graphs are displayed on the screen.

7. Analyze Results

   • For Tube 1 (Vacuum):
     • Expect constant acceleration (linear increase in velocity).
     • Slope of velocity–time graph = acceleration due to gravity (g).
   • For Tube 2 (Fluid):
     • Velocity approaches terminal value exponentially.
     • Velocity plateaus after initial acceleration.
     • Drag force rises and plateaus at a constant value.

8. Compare with Theory

   • Compute theoretical values using appropriate equations.
   • Tabulate discrepancies and identify possible sources of error.

9. Download Results

   • Download observation tables and graphs for further analysis.

10. Reset for New Trial

    • Click the "Reset" button to restore the simulation to its initial state.