[ 3 / biz / cgl / ck / diy / fa / ic / jp / lit / sci / vr / vt ] [ index / top / reports ] [ become a patron ] [ status ]
2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

View post   
File: 29 KB, 537x356, WiTricity-iMac-Charge-1-537x356.jpg [View same] [iqdb] [saucenao] [google]
5975417 No.5975417 [Reply] [Original]

Hi,I've recently figured out about Witricity but I just don't believe it, do you know some physic demostration about how it works? if its true, it has to have formulas and a good explication about why isn't this used in our times

>> No.5975426

You create some magnetic flux by running strong sin waves through an electromagnet. This induces a current in nearby inductors; it's called electromagnetic coupling. It can't be done without losing a lot of energy. I build a device like this years ago in university and powered up a 2v 30mA led at 60cm using an oscillating electromagnet fed by 12v 3A.

Technology like this is alright for charging your cellphone (slowly) at a few meters. It's not going to produce power for large appliances like desktop PCs and toasters.

>> No.5975439

its a thing but there are pretty massive efficiency hits when you do it, like 50 or 60% over a few feet of range

>> No.5975678

>>5975417
>a good explication about why isn't this used in our times
It doesn't provide the theoretical wireless charging because you still need to plug in the mat, and the mat is larger and more expensive than a wired charger that would do the same job. When you think about it, it simply doesn't make anything simpler or more convenient.

>> No.5975684

It's just another wireless charging mat. It's for people that are too lazy to plug a cord into their device.

Wireless charging is most efficient when your device is touching the mat. Even then it is less efficient than wired charging.

It's an interesting concept, but not that practical.

>> No.5975740

>>5975417

Wireless charging mats are pretty common devices, and there is no reason you should see them as original.

I used to have a watch that was programmable and stored data; advanced for it's time, 25 years ago or so. The watch was fitted on an input keyboard which made no electrical connection; induction coils sent binary data into it, that was all. (2 coils on keyboard pad where it fit, 2 coils in the watch)

Even more common, though, it the regular transformer, even the common power brick: electricity is converted in a transformer without any direct contact inside.
A transformer is basically a ring of metal, and on one side a number of insulated coils of wire wound, on the other a different number of insulated windings.
Electricity is transferred by the magnetic flux on the metal ring, and not by any metallic connection. It happens twice in every brick.