Materials Flashcards
What is Hooke’s Law
The applied force is proportional to the extension. F=kx force spring constant and extension
What is elastic deformation
When the material returns to its original shape after the force is removed
what is plastic deformation
when the material does not return to its original shape after the force is removed
What is ultimate tensile strength
greatest amount of stress that a material can withstand before reaching breaking point
what are tensile forces
forces that produce extension
How do you work out the absolute uncertainty
half the range of a data set
How do you work out the percentage uncertainty
divide the absolute uncertainty by the value and times by 100
Define Stress
Stress is defined as the force per unit area applied to the material.
Define strain
Strain is defined as the ratio of a material’s deformation to its original length
What is Young’s modulus
Young’s modulus is the ratio of stress to strain, and it’s constant up to the material’s limit of proportionality. (indicates how stiff a material is)
what is the experiment for young’s modulus
Attach a thin wire sample of known length (l) and cross-sectional area (A).
Gradually add weights to the wire.
Measure the extension distance (x) for each weight.
Calculate stress and strain values.
Plot the stress-strain data.
The gradient of the linear part equals Young’s modulus (E).
how are springs calculated in series
1/k(T)=1/k(1)+1/k(2)
how are springs calculated in parallel
K(t)=K(1)+K(2)
Define density
Density indicates how closely packed or concentrated a material is
What makes something float or sink?
An object’s ability to float or sink in a fluid is based on its average density relative to the fluid’s density.
