Sections
Glossary

Glossary

deformation
change in shape due to the application of force
drag force
FDFD size 12{F rSub { size 8{D} } } {}, found to be proportional to the square of the speed of the object; mathematically
5.48 FDv2FDv2 size 12{F rSub { size 8{D} } prop `v rSup { size 8{2} } } {}
5.49 FD=12Av2,FD=12Av2, size 12{F rSub { size 8{D} } = { {1} over {2} } Cρ ital "Av" rSup { size 8{2} } } {}
where CC size 12{C} {} is the drag coefficient, AA size 12{A} {} is the area of the object facing the fluid, and ρρ size 12{ρ} {} is the density of the fluid
friction
a force that opposes relative motion or attempts at motion between systems in contact
Hooke's law
proportional relationship between the force FF on a material and the deformation ΔLΔL it causes, F=kΔLF=kΔL size 12{F=kΔL} {}
kinetic friction
a force that opposes the motion of two systems that are in contact and moving relative to one another
magnitude of kinetic friction
fk=μkNfk=μkN size 12{f rSub { size 8{k} } =μ rSub { size 8{k} } N} {}, where μkμk size 12{μ rSub { size 8{K} } } {} is the coefficient of kinetic friction
magnitude of static friction
fsμsNfsμsN size 12{f rSub { size 8{s} } <= μ rSub { size 8{s} } N} {}, where μsμs is the coefficient of static friction and NN is the magnitude of the normal force
shear deformation
deformation perpendicular to the original length of an object
static friction
a force that opposes the motion of two systems that are in contact and are not moving relative to one another
Stokes' law
Fs=6πrηvFs=6πrηv size 12{F rSub { size 8{s} } =6πrηv} {}, where rr is the radius of the object, ηη is the viscosity of the fluid, and vv is the object's velocity
strain
ratio of change in length to original length
stress
ratio of force to area
tensile strength
measure of deformation for a given tension or compression