**Instead of calculating why we not measure the stress?**

For.e.g

To check the** temperature** of water we need** thermometer**.

**Ammeter** used to measure the** electric current,**

**Anemometer** used to measure the **wind speed**,

Astrolabe used to measure the** latitude and altitude of celestial body**,

**Audiometer** used to measure the** hearing purpose.**

**Instead of calculating why we not measure the stress?**

Barometer used to measure the pressure,

there are to ways to know the value of anything i.e either you calculate or measure.

Like, In ancient time , instead of measuring we use to calculate the blood pressure of patient.

so from above , we can get the idea to measure the stress of material by using stress measuring device .

As we know , no practical possible without theory and theory based on observation.

Application:

stress measuring device can help to know about deformation occur on material by applying load at per unit area.

In engineering ,

stress is a internal resistive force to the deformation per unit area.

σ=p/A

where,

σ=stress

P=load

A=Area

There are 3 type of stress ,

- Tensile stress
- Compressive stress
- Shearing stress

So like that putting a theoretical formula and by designing and programming we can make stress measuring device.

**Difference between the pressure and stress,**

Normally , we say that” pressure is stress”

But its not like that , for any machine

stress is a internal resistive force to the deformation per unit area.

σ= applied load/cross section

unit – N/m²

But,

Pressure is force per unit area.

P=F/A

unit-N/m²

Due to stress , the pressure will not develop .

But, Due to pressure the stress will develop

so we cannot say that pressure and stress and same .

So Basically the conclusion is pressure has measuring device ,but stress do not have measuring device.

Although ,

we have stress measuring machine but not a stress measuring device.

S0, by using stress measuring device we can get the stress value of any material at any direction.