Procedure Of The Experiment #1 1- AC adapter connected to power jack on the control box. 2- One of the timer switch plugs connected to the photogate port on the control box. 3- Included cable used to connect signal to drop box jack on the control box to control box jack on the drop box. 4- Active/inactive switch on the control box set to active. 5- Time-of-flight pad placed directly below the drop box. 6- The first ball(yellow ball) hanged from the drop box magnet. 7- Xplorer GLX set as timing device. 8- The object suspended to the drop box to height of 1.5 meters. 9- The object released from the drop box 3 times. 10- Fall times were measured. Each step repeated with large hallow plastic ball. And this data obtained. Height: 1.5 meters .Yellow Nylon Ball Large Hallow Plastic Ball t1 (s) 0,562 s 0,566 s t2 (s) 0,554 s 0,600 s t3 (s) 0,556 s 0,567 s tave (s) 0,557 s 0,578 s