Cavendish Torsion Balance - Automatic Gravitational Constant Measurement by 3B Scientific

The Cavendish torsion balance showcases the gravitational force between two masses, enabling the calculation of the gravitational constant. With a swift oscillation period of 2-4 minutes, this constant can be accurately determined within a single lesson, surpassing a 10% precision.

• Torsion Pendulum Core: A light bar with two small lead spheres, suspended horizontally from a thin wire
• Initial Movement: Attraction between the two small spheres and two larger ones moves the apparatus from its rest position
• New Position Vibration: Rotating the two large spheres causes the torsion balance to vibrate around a new rest position
• Motion Measurement: A capacitive differential sensor measures the rotary motion, suppressing noise and vibration components
• Data Recording: The output is recorded using a computer
• Data Export: For evaluation, data can be exported to a spreadsheet
• Motion Demonstration: Alternatively, the motion can be shown using a light pointer