Home > Preview
The flashcards below were created by user
Anonymous
on FreezingBlue Flashcards.

Stress is ..
The force applied to an object divided by the area over which the force is applied.
Stress = F/A
Note that to distinguish from pressure, we use the unit N/m^{2} instead of Pa.

To distinguish stress from pressure, ...
We use the unit N/m^{2} instead of Pa.

Strain is the..
Fractional change in object's shape. Strain is a ratio of change, so it has no units.
Strain = delta dimension / original dimension.

Basically stress is what done to an object, strain is what the object responds.

The modulus of elasticity is..
 Since stress and strain are proportional to each other.
 The proportionality is given by modulus of elasticity.
Modulus of elasticity = stress / strain

Stress and strain are ______ each other.
Proportional to.

The point that an object is bearing maximum stress while it can be reverted into its original shape is ____.
Yield point.

The modulus of elasticity most accurately describe the ratio of stress to strain when..
The stress is less than yield point.

The stressstrain ratio is not described accurately by the modulus when..
When the stress exceeds the yield point.

Young's modulus, Shear modulus, Bulk modulus,
What are those refering about?
(E) Young's modulus: Tensile stresss
(G) Shear modulus: Shear stress
(B) Bulk modulus: compression and expansion.
All moduli work in both direction, e.g. Young's modulus works for tensile compressive force and tensile stretching forces.
Remember that it's not the net force be used here because it might get 0 net force, instead, it is one of the magnitude of the force is used.

The equation of Young's modulus..
F/A = 1/E x ( delta h / h_{o )}

The equation of shear modulus..
F/A = 1/G x (delta x / h_{o} )

***The equation of bulk modulus..
F/A = 1/B x [delta p / (delta V / V_{o} )]

Solid ____ upon heating.
Expands.

Solids expand upon heating because..
When their molecule absorbs energy their vibration increase, thus they need more room for vibration.

