Thrust and Pressure

Thrust The force applied on a surface in a direction perpendicular to the surface Unit = Newton (N)

Pressure The effect of thrust per unit area is called pressure. Pressure =thrust/area Unit – Pascal (Pa) 1 Pa = 1 N / 1m2

Pressure depends on two factors 1.force(thrust)-more force more pressure 2.area -more area less pressure

“The same force produces less pressure if it acts on a large area but can produce less pressure if acts on a small area.”

every day observation 1.School bags have wide straps so the weight of bag may fall over a large area of the shoulder of the student producing less pressure on shoulder.

Sharp knife cuts better than a blunt knife so the force of our hand falls over a very small area of object produces large pressure.

The tractor have broad tyres so there is less pressure on ground and do not sinking to comparatively soft field.

It is easier to walk on soft sand if we have flat shoes rather than shoes with sharp heels.

The foundations of buildings and dams are laid on a larger area to produce less pressure

>A wide seat belt is provided over the wheels of an army tank. >The wooden or concrete sleepers are kept below the railway line. >A wide seat belt is provided over the wheels of an army tank.

Define thrust. What is its unit? Now answer Define thrust. What is its unit? What is the relation between pressure, force and area? Name the quantity whose one of the unit is Pascal (Pa)? Why does a sharp knife cut objects more effectively than a blunt knife? Why the tip of sewing needle is sharp? Why snow shoes stop you from sinking into snow?