Pressure and Moments

A brief PowerPoint to describe my understanding of Pressure and

Moments

Items that cause high and low pressure.

• Stiletto heels - Pumps.

• Beanbag - Chair.

The pressure formulaPressure (the symbol: P) is the force per

unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.

The diagram at right shows a sharp knife and a dull knife in contact with a surface (maybe a nice, juicy steak!). You know that the sharp knife cuts more

efficiently - Why?Notice that the sharp knife has a very small area of contact with the surface,

while the dull knife has a much larger area of contact. If both knives are pushed down with the same force, the sharp knife will exert a much greater

pressure on the surface than the dull knife - and pressure cuts.So, if you are "stuck" with a dull knife, you have to exert much more force in

order to generate enough pressure to cut your steak, right?

Moments

Force multiplied distance from pivot equals turning moment.

John Morgan