To determine the value of G. It consists of an electronic unit having four sockets and a switch to help hold or release the ball. A heavy retort stand carries a solenoid. When toggle switch is on Catch position, current flows through solenoid producing a magnetic field and holding the ball. The retort stand carries another base. The ball after being released from solenoid fall s on this base. Time taken by the ball to travel from solenoid to second base is recorded in electronic unit.
