1. Home >
2. Apps >
3. Groups >

# What is the difference between pressure and stress?

Question asked by anjali zendre in #Coffee Room on Oct 21, 2012
anjali zendre 路 Oct 21, 2012
Rank C3 - EXPERT
There pressure and stress both have same unit N/m^2.then what is difference between them.? Posted in: #Coffee Room
Abhishek Rawal 路 Oct 21, 2012
Rank A2 - PRO
Similar thread found in CE. Refer : Diference between pressure and stress? | CrazyEngineers
anjali zendre 路 Oct 21, 2012
Rank C3 - EXPERT
i have got same thing so want to shear ..
1. pressure represent intensity of external forces acting at a point. but stress represent intensity of internal resisting forces develop at a point.
2. pressure is always acts normal to the surface. but but stress may also act either normal or parallel to the surface.
3. magnitude of pressure at a point in all direction remain same. but magnitude of stress at a point in all the direction are unequal.
4. pressure can be measure by using measuring device.like pressure gauge. but stress can't be measure directly by using any device.
Portgazz 路 Nov 19, 2012
Rank E2 - BEGINNER
pressure is scalar dimension, it just has value no orientation, but stress is vector dimension, it has value and orientation...馃榿
the scientist 路 Dec 23, 2012
Rank D2 - MASTER
pressure is a general term used for force per unit area.....but stress is t erm used in case of pressures in solids.....
for hydraulic pressure we cant use the term stress...
PuneetVerma 路 Dec 24, 2012
Rank C2 - EXPERT
Pressure : Intensity of external forces acting on a body per unit area. For example : Atmospheric Pressure - Its the pressure exerted by air on surface of earth.

Stress is Internal Resistance offered by a body to external forces per unit area. Taking an example of Rubber Material. You apply some force and it deforms. But assume it doesn't deforms; then what happens, material is applying force equivalent to external force. That opposite force in termed as Internal Resistance and its ratio with area is called Stress.
G.D 路 Jan 20, 2013
Rank D3 - MASTER
basically in simple words,
1)pressure 'acts' on body whereas stresses are 'induced' or 'developed'.
2)pressure is something what we apply or gets applied on body due to external loading like torque, force; to this the internal reaction developed automatically is stress.
3) various strain gauges are available to measure stresses.
4) stress is not vector, its tensor; it has direction and orientation(plane in which it acts) as well.
lvk aditya 路 Nov 12, 2015
Rank E2 - BEGINNER
for stress it is N/M2
for pressure N/MM2
Ankita Katdare 路 Jan 8, 2016
Rank A1 - PRO
@lal Could you share your views here?
Himanshuwkc 路 Jan 8, 2016
Rank E2 - BEGINNER
In simple terms
Pain caused by love is stress. It happens from within. On the other hand pressure, my friend, is like the pain caused by a bullet. It is due to external factors.
Imagine someone thrusting a heavy object on your shoulders. That's pressure.
Imagine yourself holding a heavy object. That's stress.
Technically, there are many differences. But it'll help if you understand this.
lal 路 Jan 9, 2016
Rank A3 - PRO
Ankita Katdare
@lal Could you share your views here?
It seems like there is nothing extra I could add to this discussion. I only had an understanding that stress is an internally developed reaction to counter an external force where as pressure is an external force acting per unit area.

Although it has to be understood that stress can remain in a material even when no external force is acting on the body continuously. Probably a good example is when stress remains in metals after heat treatment processes or forging. Those metals have to undergo a stress relieving process in which the material will be heated to critical temperature so that their grain structure realigns to attain a stress free state.

## You must log-in or sign-up to reply to this post.

Click to Log-In or Sign-Up