Solids Evaluation (12.10.2020) Flashcards
atoms in a solid are arranged in a regular array called a ____
crystal
if you shine an x-ray beam on a solid and it produces an____ pattern, this is evidence of the crystalline nature of the solid
x-ray diffraction
solids that do not have atoms arranged in a regular array are called _____
amorphous solids
____the amount of mass per unit of volume of material
density
density =
mass/volume
unit of density is ____ or ____
kg/m^3 or g/cm^3
weight density =
weight/volume
unit of density in weight density is ___
N/m^3
weight density =
9.8m/s^2 times density
density depends upon which two things?
mass of the atoms, spacing between the atoms
density is a property of the material, so
it does not matter how much material you have
an object subjected to external forces may undergo changes in ___ and/or ____
shape; size
A body’s ____ is a measure of how much it changes when a deforming force is exerted on it and how well it returns to its original shape
elasticity
materials that do not return to their original shape are ___
inelastic
steel is (more/less) elastic than rubber
more - it regains original shape better
Hooke’s Law
the extension of a spring is directly proportional to the force applied to it
Hooke’s Law: F =
kx
Hooke’s Law: F ~
extension or change in position
when something is pulled it is ____
tension
when something is squashed it is in ____
compression
often construction uses an ____ with a cross section shaped as letter I
I-beam
the I-beam maximizes ____because the top (under ___) and bottom (under ___) have the most material
strength; tension; compression
an I-beam minimizes ____ because the middle of the beam that is not under stress has the least material
weight
