# Homework Help: Lenz' Law toy

1. Mar 17, 2016

### pompom15

1. The problem statement, all variables and given/known data
There is 4 neodynium magnets. It is 0.7 inch magnet. A 15,000 RPM motor. It does not hover. I am trying to make a eddy current to make it hover

1. The attempt at a solution
Getting a copper plate, having a better magnet.

2. Mar 18, 2016

### Simon Bridge

How are you trying to get it to hover?

3. Mar 18, 2016

### pompom15

I am making the magnets spin.

4. Mar 18, 2016

### Simon Bridge

How are you trying to get the magnets to spin? In what way do you want them to spin?

First you say "it does not hover" but do not say what you want to hover or why you would expect it to hover ... now you say you just want the magnets to spin. Which is it?
You need to be more detailed and consistent than that or we cannot help you. Please recall that none of us can see what you've done and there are a numbers of things you could have tried (including a large number of wrong things). Please help us to help you.

5. Mar 18, 2016

### pompom15

I am trying to get the disk to hover. It is spinning clockwise. It just falls to the ground. The battery does not have full power.

6. Mar 18, 2016

### Simon Bridge

Not enough information.
Imagine that I have not seen what you have attempted and you need to describe it to me so that I have an accurate mental picture. I have seen many different ways to use lenzes law for levitation so I just need to work out which method you are trying. So far "I spin the magnet and it falls down" is unhelpful - there are an any number of ways to spin a magnet and all I can tell from this description is that you are using one of the millions of wrong ways. Don't make me guess.

So: what is it about the assembly you have that leads you to think it should be able to levitate?
I need details. Is it a secret?

Last edited: Mar 18, 2016
7. Mar 19, 2016

### pompom15

The way I assemble it is by making a hole on a bottle cap that the motor can fit through it. The motor can spin the bottle cap like this. The video shows you how I am trying to make it hover. I am trying to make it hover like the Hendo White Box or the Hendo Hoverboard. The bottle cap is a big one. Like a milk jug bottle cap. The way it falls down is it just falls down like any thing else.

8. Mar 19, 2016

### Simon Bridge

Again: not enough details. Your rig is clearly not exactly like this one.

You have to describe what you are doing in detail - starting from the video, what are you doing differently?
i.e. that one has 8 magnets, you have only mentioned one. So how many are you using?
Guessing: you have mounted some magnets around the outside of a plastic disk - which way up? Are they all facing the same way? What are the dimensions? How strong are the magnets? How heavy is the whole thing? What does the whole thing consist of exactly?

"A big one like..." does not tell me anything about size: imagine I am in another country and we don't have milk jugs like you do. Do you have rulers where you live?

It is far too difficult to get in formation from you for anyone to be able to help you out.

Last edited: Mar 19, 2016
9. Mar 19, 2016

### pompom15

They are in the north south formation. The bottle cap is 4 x 4.5 cm. It is facing in front. By in front I mean facing up with out the indent. The thing has 4 neodynium magnets 0.112 inches thick. It is 0.12 inches tall. It is 0.7 inches wide. 6 lb max pull. The motor stalls at 200 grams.The bottle cap is 4 grams. The magnets each weigh .1023 lbs. 453.592 is how much grams in a pound. The wires are stranded. It uses a 9 volt battery. The copper sheet is 0.025mm thick. I got the the info from the magnet on the store website. It is a hardware store. The motor is 15,000 RPM. The whole thing weighs 189.609996.

10. Mar 20, 2016

### Simon Bridge

Sounds like you've avoided the obvious problems ... so you have the magnets with two N-side down and two S-side down, alternating?
It drops like there is no levitation at all? Hmmm... maybe it's just too heavy?

Try the obvious first:
Have you checked the magnets by dropping them through a metal pipe?
As a proof of concept, try using the motor to rotate an aluminium can about it's axis, lower a single magnet close to the rotating can to see if it will levitate it's own weight.