Levitation and magnetism

 

Levitation toys are common. The work by magnetic repulsive forces.

 

We can make our own by careful placement and alignment of magnets as shown on the right.

Click to see what you will need.

Construct the base as shown.

Carefully place the round magnets on the pencil so that they line up with the magnets on the base.

 

The video on the right shows a completed toy.

What forces are acting on the suspended toy?

These forces are

 

 

By adding to the levitation toy and making it look like a plane or boat you can achieve impressive results, however, by doing so stability is compromised, as shown in the video on the right.

 

 

 

A counter weight is necessary to stabilise the toy otherwise it rotates around its longtitudinal axis. As shown in the video on the right, a weight in the form of plasticine can make the toy very stable. This is similar to ballast on a racing yacht.

 

 
Explain how placing a weight beneath the levitation toy, as shown on the right, makes it more stable. You may refer to the unit on ballast.

Two forces are shown acting on the pencil on the right.

A is and B is

The pencil is motionless suspended in midair. Forces A and B are