Properties of materials (12) Flashcards Preview

Physics A-Level AQA definitions > Properties of materials (12) > Flashcards

Flashcards in Properties of materials (12) Deck (15)
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1
Q

Weight

A

the pull of gravity on an object. W=mg

2
Q

Compressive forces

A

are forces that tend to squeeze an object and reduce its size in the direction that the forces are applied.

3
Q

Tensile forces

A

are forces that act to pull or stretch an object.

4
Q

Spring constant, k

A

a measure of how hard it is to bend or stretch a spring. A large spring constant means that the spring is stiff. Units of Nm-1.

5
Q

Extension

A

is the length a material has stretched when a load is added. It is calculated by subtracting the original length of the material from the length when stretched.

6
Q

Limit of proportionality

A

is the endpoint of the linear section of a force-extension graph.

7
Q

Elastic limit

A

is the load above which a material is permanently deformed.

8
Q

Elastic (material)

A

a material is said to be elastic when it returns to its original dimensions once the applied load is removed.

9
Q

Plastic (material)

A

a material is said to be plastic when it is permanently deformed and does not return to its original dimensions once the applied load is removed.

10
Q

Ductility

A

ductile materials can be formed into wires by stretching them. They show ductility. Neck when fracturing.

11
Q

Brittle

A

a brittle material is one that shows little, or no, plastic deformation before breaking. Clean fracture.

12
Q

Elastic strain energy

A

is the energy stored by stretched materials.

13
Q

Tensile stress, σ

A

=force/(cross-sectional area) (units Nm-2)

14
Q

Tensile strain, ε

A

=extension/(original length) (unitless; sometimes expressed as percentage)

15
Q

Young Modulus, E

A

is a measure of the stiffness of an elastic material. It does not depend on the dimensions of the sample being tested. Measured in Pa or Nm-2. =stress/strain