Watch your students "gravitate" toward physics!
Dr Fred Trexler, Professor of Physics at Spring Arbor University, has used the Computerized Cavendish Balance. He says, "every one knows that gravity works in the vertical direction, but with the Computerized Cavendish Unit I can demonstrate to students that it works in a 'horizontal' direction as well. The students are convinced by the end of this short demonstration that their mass does indeed exert a gravitational force."
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the students shift position (right) to drive the boom in the opposite direction.

| Dr. Ken Hayes of Hillsdale College has used the unit for several years: "I am impressed with the accuracy and ease of use of the unit, especially that data can be taken in a single lab period. In fact, some students have chosen to do advanced projects with the Computerized Cavendish Balance in our independent study course." |
![]() Resonant drive from 2 groups of students. Students ranged from 0.8m to 2m from corners of the apparatus. |
| Computerized Cavendish Balance TEL RP2111 $2,089.00 | |
![]() The large lead spheres drive the boom at its resonant frequency (period=3.9 min) for about 14 minutes. Then the masses were positioned in the center so they had no net torque on the boom. The free oscillation decay is shown from 14 minutes to 27 minutes. | ![]() Displacement due to two extreme positions of the large lead balls. |





