How do you creat a void in air or reduce the density or resistance of air ?

Question

other than going up in altitude, sea level .Possably using heat gases microwave type waves.
Also pose the question to water.

Answer 1

Make the flow in front of your object turbulent by sending something solid right in front of it (like "drafting" in NASCAR) or by putting a rough shape on the object (like dimples on a golf ball).

You could also heat it up, but that's not very practical in most cases.

Answer 2

You just heat it. Temp goes up, volume goes down. For air and water. When water freezes it expand a bit though, like 10%, thats an exception

Answer 3

heat it. almost everything expands, and hence becomes less dense, if you do so. water is a common substance that has certain temp range exceptions to this. warming water from
30 fahrenheit to 33 fahrenheit will actually RAISE the density quite a bit ;) ( so watch out for phase changes)

Answer 4

Vacuum- Simple and efficient.

Electromagnetic Alpha gamma particle wave or WAGP - The idea is simple enough but creation of such a device is extremely difficult and dangerous.

Answer 5

Take a sturdy container, pump out air/water

Answer 6

you spin it

The higher you go the thiner the air
The deeper you go there is more air in h2o

Answer 7

raise the temperature