Abstract
An electronic system based on a photo gate and an electronic switching circuit is designed for studying simple pendulum at large angles. The detailed of the system operation is studied, the pulse measurements performed on a CRO screen for five displacement amplitude angles of 5, 10, 15, 20, and 25 degrees, and the technical problems associated with the measurement process is treated. Results show that calculated acceleration of gravity with acceptable magnitudes can be obtained for small displacement angle of 5o compared with the real value of the local acceleration of gravity; the relative error is 0.01617 %. Instantaneous time period, amplitude decay, and maximum velocities are measured and used for error handling in the calculation of the acceleration of gravity. In order to overcome the problem of the operating time of the relays which are used in the electronic circuit switch, taking 80 periods for manual measurements have been proved to be useful in decreasing errors in the calculation of acceleration of gravity.