SP2e Bending and Stretching Flashcards
An elastic object may become compressed when ?
forces are exerted on it.
When a force pulls on an elastic object and it extends, it is ?
under tension as it is stretched.
The greater the force on an elastic object the ?
more it extends.
What leads to objects becoming deformed?
tension and compression.
Elastic ?
can be stretched or compressed and then returns to original shape - no pernament deformation.
Inelastic ?
keeps new shape after the forces are removed - permanently deformed.
Extension of a spring is change in ?
length when tension or compression forces are applied.
Extension (or compression) =
new length - original length
Hooke’s Law ?
for an elastic object below its limit of proportionality, the force is directly proportional to the extension F ∝ x
Relationships become non-linear when?
limit of proportionality is reached.
If more force is applied, the spring ?
reaches its elastic limit and behaves inelastically - it is permently deformed.
Rubber bands have what type of relationships ?
non-linear relationships between force and extension.
Explain the force - extension relationship for copper
copper is ductile and malleable so can be reshaped by hammering without breaking. When stretched beyond its elastic limit, it continues to have its new shape.
Explain the force - extension relationship for rubber
doesn’t obey Hooke’s Law and remains elastic until it breaks.
Explain the force - extension relationship for glass
is brittle and obey Hooke’s Law until it breaks.
