OCR A LEVEL PHYSICS
B MATERIALS NEW!!!
NEW!!!
Brittle - ANS✔✔---Breaking without permanent deformation by crack
propagation. Snaps. Examples are: Biscuits or ceramics
Elastic - ANS✔✔---Can be stretched and returns to its original shape without
breaking permanent deformation. Example: Slinkey
Stiff - ANS✔✔---Difficult to bend or stretch. High Young's modulus. Example:
Outside of a crash helmet
Hard - ANS✔✔---Difficult to scratch or indent. Example: Diamond
Ductile - ANS✔✔---Can be drawn into wires, Plastic behaviour. Example:
Copper
Malleable - ANS✔✔---can be hammered or rolled into shape - Plastic
behaviour. Example: Gold
, Plastic - ANS✔✔---Can be made to change its shape without permanent
deformation. Example: Plastic
Strong - ANS✔✔---Difficult to break. Requires large stress to break.
Example: Steel beams
Tough - ANS✔✔---Absorbs a large amount of energy before breaking
through plastic deformation. Example: Kayak
Hooke's Law - ANS✔✔---Extension is directly proportional to force until the
spring reaches it's elastic limit.
F = kx
Spring network - ANS✔✔---Single spring:
-F = kx
Springs in series:
For the same amount of force, we get double the extension.
k is halved to balance equation: F = (k/2)x
Springs in parallel:
For the same amount of force, we get f/2 for each spring.
K is doubled to balance the equation: F = (2k)x
Stress definition - ANS✔✔---the tension divided by the cross-sectional area
σ = F/A, Units: Nm^-2/ Pa
Strain definition - ANS✔✔---The extension divided by the original length
ε = x/L, No units
Stress graph - ANS✔✔---
B MATERIALS NEW!!!
NEW!!!
Brittle - ANS✔✔---Breaking without permanent deformation by crack
propagation. Snaps. Examples are: Biscuits or ceramics
Elastic - ANS✔✔---Can be stretched and returns to its original shape without
breaking permanent deformation. Example: Slinkey
Stiff - ANS✔✔---Difficult to bend or stretch. High Young's modulus. Example:
Outside of a crash helmet
Hard - ANS✔✔---Difficult to scratch or indent. Example: Diamond
Ductile - ANS✔✔---Can be drawn into wires, Plastic behaviour. Example:
Copper
Malleable - ANS✔✔---can be hammered or rolled into shape - Plastic
behaviour. Example: Gold
, Plastic - ANS✔✔---Can be made to change its shape without permanent
deformation. Example: Plastic
Strong - ANS✔✔---Difficult to break. Requires large stress to break.
Example: Steel beams
Tough - ANS✔✔---Absorbs a large amount of energy before breaking
through plastic deformation. Example: Kayak
Hooke's Law - ANS✔✔---Extension is directly proportional to force until the
spring reaches it's elastic limit.
F = kx
Spring network - ANS✔✔---Single spring:
-F = kx
Springs in series:
For the same amount of force, we get double the extension.
k is halved to balance equation: F = (k/2)x
Springs in parallel:
For the same amount of force, we get f/2 for each spring.
K is doubled to balance the equation: F = (2k)x
Stress definition - ANS✔✔---the tension divided by the cross-sectional area
σ = F/A, Units: Nm^-2/ Pa
Strain definition - ANS✔✔---The extension divided by the original length
ε = x/L, No units
Stress graph - ANS✔✔---
