This physics extended essay investigates the acceleration of a falling neodymium magnet inside an aluminium pipe when the number of magnets are changed from 15 and the radius of the pipe is varied from 2.028-4.415 cm. When a magnet moves near a non-magnetic conductor, it will induce eddy currents within the conductor thus creating its own opposing magnetic field. These eddy currents can be applied as an efficient and long-lasting braking system for trains such as the new Jakarta Mass Rapid Transit trains in Indonesia. Both number of magnets and radius of the aluminium pipe are variables that affect the acceleration experienced by the moving magnet. The research question extracted from those variables is “How does the radius of a pipe and magnetic field strength affect the acceleration of a falling magnet inside an aluminium pipe?”

The neodymium magnets were dropped from the top of an aluminium pipe that is suspended on a wall using duct tapes. Two photogates are held using a clamp and a retort stand at the entrance and the exit of the pipe. The photogates measure the time taken for the magnets to travel through the entire length of the pipe. The pipes used had different radii of 2.028, 2.540, 3.048, 3.840, and 4.415 cm. Also, the number of magnets dropped varied from 1 magnet, 2 magnets, 3 magnets, 4 magnets and 5 magnets. The acceleration was calculated based on the average time.

In conclusion, an increase in pipe radius will increase the acceleration of the falling magnets while increasing within the conductor thus creating its own opposing magnetic field. These eddy currents can be applied as an efficient and long-lasting braking system for trains such as the new Jakarta Mass Rapid Transit trains in Indonesia. Both number of magnets and radius of the aluminium pipe are variables that affect the acceleration experienced by the moving magnet. The research question extracted from those variables is “How does the radius of a pipe and magnetic field strength affect the acceleration of a falling magnet inside an aluminium pipe?”

The neodymium magnets were dropped from the top of an aluminium pipe that is suspended on a wall using duct tapes. Two photogates are held using a clamp and a retort stand at the entrance and the exit of the pipe. The photogates measure the time taken for the magnets to travel through the entire length of the pipe. The pipes used had different radii of 2.028, 2.540, 3.048, 3.840, and 4.415 cm. Also, the number of magnets dropped varied from 1 magnet, 2 magnets, 3 magnets, 4 magnets and 5 magnets. The acceleration was calculated based on the average time.

In conclusion, an increase in pipe radius will increase the acceleration of the falling magnets while increasing the number of magnets will decrease the acceleration. This is caused by the time taken for the magnet to increase as the pipe radius is increased as well as the number of magnets.

Grade: B