The PASCO Drop Box magnetically suspends a metal object and drops it when externally triggered. The triggering device can be a photogate or a push-button timer switch. You can also trigger it without an external device by pressing a built-in button. The Drop Box is designed for use with PASCO systems such as the Shoot-the-Target Accessory and the Discover Free Fall System.
The Drop Box holds the object with a permanent magnet. To cause the object to drop, current flows through a coil canceling the magnetic field.