Home SCIENCE Magnetic Items Near An MRI Scanner Magnet? Practical Demonstration

Magnetic Items Near An MRI Scanner Magnet? Practical Demonstration


Fun, games and safety implications with a 4 tesla (T) MRI magnet that was about to be decommissioned. Note how magnetic objects let loose tend to oscillate along the magnet bore.

source/image: practiCalfMRI

That’s because the peak magnetic field gradients are at either end (near the magnet face), causing peak acceleration as the object enters, followed by progressively damped changes of direction.

source/image: practiCalfMRI

Experiments showing the magnetic field strength conducted by scientistsThey use a stapler, a wrench and then an office chair to demonstrate power.As the tensile force on the chair reaches 1,700lbs, the headrest snaps off.


The chair is connected to the gauge, and you can quite clearly see it being sucked in towards the scanner.At 700lbs of force, the chair now enters the scanner.

Then the force reading ticks past 1,300lbs and at 1,700lbs a loud crash sees the back of the headrest fly off.The video ends with one of the scientists showing the reading having reached 2,000lbs, in their words, ‘about the same (weight) as a small car.

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