Here, there and everywhere

How much does a falling magnet weigh?

If you drop a strong magnet down an aluminium tube, it falls surprisingly slowly. As it falls, it induces electrical currents in the tube. Those currents themselves have their own magnetic fields, which arrange themselves to resist the motion (Interested? Click here for a full explanation).

Watch the weighing scales as it falls. The weight of the magnet contributes to the weight of the tube as it falls, even though it’s not actually touching the sides of the tube.

As it falls, because it isn’t accelerating at full speed as it if it were falling normally, the tube must be supporting it. If there’s a force holding the magnet up, there must be an equal force acting downwards on the tube. That force is what the scales record. 

How much does a falling magnet weigh?

If you drop a strong magnet down an aluminium tube, it falls surprisingly slowly. As it falls, it induces electrical currents in the tube. Those currents themselves have their own magnetic fields, which arrange themselves to resist the motion (Interested? Click here for a full explanation).

Watch the weighing scales as it falls. The weight of the magnet contributes to the weight of the tube as it falls, even though it’s not actually touching the sides of the tube.

As it falls, because it isn’t accelerating at full speed as it if it were falling normally, the tube must be supporting it. If there’s a force holding the magnet up, there must be an equal force acting downwards on the tube. That force is what the scales record.