Deformation of solids

Question 1

strong

Answer 1

can withstand much force with minimal extension

Question 2

stiffness

Answer 2

resistance to deformation

Question 3

toughness

Answer 3

can absorb much energy before breaking, much plastic deforming before breaking

Question 4

ductility

Answer 4

ability to be drawn into wires

Question 5

malleability

Answer 5

able to bend without cracking

Question 6

hardness

Answer 6

resistance to scratching and pressure

Question 7

brittle

Answer 7

material breaks with little stress

Question 8

elastic

Answer 8

returns to original shape when load is removed

Question 9

plastic

Answer 9

doesn’t return to original shape and has permanent deformation

Question 10

yield stress

Answer 10

minimum stress at which material undergoes plastic deformation

Question 11

compression

Answer 11

two coplanar forces act into object

Question 12

compressive deformation

Answer 12

change of object shape due to compressive forces

Question 13

elastic limit

Answer 13

force beyond which object starts deforming plastically instead of elastically

Question 14

elastic potential energy

Answer 14

energy stored in an object when its stretched. Equal to work done to stretch object. Area of force extension graph

Question 15

extension

Answer 15

increase of an objects length

Question 16

Hooke’s Law

Answer 16

extension of elastic object is proportional to force applied up to limit of proportionality

Question 17

limit of proportionality

Answer 17

point at which stress is so much that Hooke’s law no longer applies

Question 18

spring constant

Answer 18

constant of proportionality for force and extension. More constant means more force needed

Question 19

strain

Answer 19

ratio of objects extension to original length. Ratio of two lengths so no unit

Question 20

stress

Answer 20

force acting per unit area. In pascals

Question 21

tension

Answer 21

result of two forces acting on an object opposite outwardly

Question 22

tensile strain

Answer 22

extension of object divided by original length

Question 23

tensile stress

Answer 23

internal resistance of an object against a force that acts to deform it. Force applied per unit cross-sectional area

Question 24

young modulus

Answer 24

ratio of stress to strain for given material. Unit in pascals