forthex

High-School-Physics-Free-Body-Diagram Time! Free body diagrams are used to show forces on one or more objects.

Here, we see a (really shitty MS Paint) free body diagram, Where G is the force of gravity on the the block at its centre of mass, and N is the normal force of the ground on the block.

The force of gravity is probably easy to understand (stuff falls down), but what exactly is the "normal force"? Well, the block isn't falling though the ground, is it? If the ground wasn't there, it would just keep falling, right? So, because the block is stationary (ie not moving, or more importantly accelerating), this means that the ground has to be applying a completely equal and opposite force on the block! The equal and opposite phrase might be familiar to some of you, as it's Newton's Third Law of Motion.

So, what would a free body diagram look like if we wanted to easily move around a pinball machine with giant electromagnets?

Here, the two G forces are the force of gravity acting on the handcart and the pinball machine, N is the normal force of the handcart on the pinball machine, and M is the collective magnetic forces pushing the cart up and away from the ground.

To levitate the handcart and its load, off the ground and into the air a particular distance, these magnetic forces must be larger than the forces of gravity on the handcart and its load. When the handcart is in the air at a particular distance, the magnetic forces have to be equal to the collective forces of gravity. You would then, theoretically, be able to push around the handcart horizontally with ease.

The floor would have to be magnetized (somehow), as would the handtruck.

So, what I'm getting at, is the the theoretical physics is there, BUT it's going to be impractical, prohibitively expensive, and possibly destructive implement.

What about doing it Vinnie's way?

Here, N is the normal force of the ground on each wheel, G is the force of gravity on the handcart and the pinball machine, and M is the force of magnetism on the pinball machine and the handcart. You'll notice the magnetic force pushing up on the pinball machine is also equally pushing down on the handcart, much like Normal forces do. So, as you move the handcart around, you would notice that it fells just as heavy as if you didn't use the magnets at all. Actually, it would be heavier, because of the installed electromagnets.