Magnetic Force and Vastu:

The entire universe is a magnetic field and all the planets and stars are related to each other by magnetic waves.
A magnet has two poles , North Pole and South pole, similarly the earth also has two poles , North Pole and South pole.
All magnets attract and repel is  produced by the arrangement of atoms within the magnetic material . 
The magnetic north pole of the Earth is the direction in which all compasses point.
Applying this , one should never sleep with the head facing in North direction.
When our head is in North , the earth's magnetic force and our body"s magnetic force repel  and result in problems like sleeplessness , headaches, tension and bad dreams.