The effect is called the Lenz Effect. The moving magnet causes small magnetic fields, called eddy currents, to form in the metal (brass, aluminum foil/tube ...). These eddy currents have their own magnetic field (all electrical currents do). This is what is interacting with the moving magnet.
1 Limited use: The Angel Card can only be used in Victoriaâs Secret and PINK stores. 2  While you may also use the card at Bath & Body Works stores, you will not earn Angel Reward points on those purchases.
PLEASE READ THIS IF YOU STAY IN HOTELS AND ARE GIVEN A CARD FOR ACCESS TO YOUR ROOM. This is a really useful information for anyone who goes on holiday where the hotel uses key cards xxx Always take a small fridge magnet on your holiday, they come in handy at the end of it.