Affect Of Forces On Materials

Question 1

Tensile force

Answer 1

• increase the length of the material on which it acts

Question 2

Compressive force

Answer 2

Decrease the length of the material on which it acts (compressive)

Question 3

Shear force

Answer 3

Can cause material to bend, slide or twist

Question 4

Strain

Answer 4

Change in length divided by original length

Question 5

Elasticity

Answer 5

Ability of a material to return to its original shape on the removal of an external load

Question 6

Plasticity

Answer 6

Property of a material of being permanently deformed by a force without breaking

Question 7

Ductility

Answer 7

material can be plastically deformed without fracture. Ability of a material to be drawn into wire under tensile load, without fracture.

Examples: mild steel, copper, gold

Question 8

Brittleness

Answer 8

When a material fractures without prior warning (i.e no plastic deformation)

Brittleness is a lack of ductility

Examples: cast iron, glass, concrete, brick, ceramic

Question 9

Yield stress

Answer 9

Limit of elastic behaviour, beyond this point the material will be plastically deformed

Question 10

Ultimate tensile strength

Answer 10

Max stress a material can withstand before fracture