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## Pressure

Definition of pressure:

Pressure is defined as force per unit area

Pressure=force/area

(P=F/A)

When force is in newtons(N) and area is in m2, then pressure P is in N / m2 or pascal (Pa).

The following numerical example compares the pressure exerted on the floor by a girl of weight 400N, when she wears a pair of shoes with high heels(having small area of contact with floor) and when she wears a pair of slippers with large area of contact with floor.

• With high heels

Force=400N
Area of heels=100X10-6m2  (assumed)
Pressure=400/100X10-6
=4X106 N/m2 or Pa

• With slippers.

Force=400N
Area of slippers=3000X10-6m2
Pressure=400/3000X10-6
=0.13X106 N/m2 or Pa

Area of slippers is 30 times greater than area of heels. So pressure is 30 times greater in case of heels.

Hence when area is small pressure will be higher.

 Amaan Said : Insufficient information 26/11/15 01:23 PM

 Uwase Sandrine Said : A picture could help with again more details 23/01/15 07:58 AM

 Uwase Sandrine Said : it would be good if it was detailed with a few examples and more explanation but thankx anyway saved my life 23/01/15 07:49 AM

 abdirahman Said : i really need more details on pressure!! 03/05/12 08:17 AM

 Zoyaa Said : Yeah good explanation but i need more in detail. Anyways Thank You :)------------------------------------------------------------------------------------- Admin Replied: Thanks Zoyaa, for your comments. We will try to add more details very soon. 09/04/12 06:17 PM

 Zeenat Said : Good understanding of pressure, but it will be good if few more examples are there.------------------------------------------------------------------------------------- Admin Replied: Thank you for your comment. We are trying our best to make it possible. 20/12/11 09:42 AM