2.2.1

Question 1

what is newtons first law ?

Answer 1

a body will remain at rest or continue to move unless acted upon by a force

Question 2

what is a moment ?

Answer 2

turning effect produced by a force around a objects fulcrum

Question 3

what two things have a effect on the force applied to a spanner ?

Answer 3

1. magnitude of force
2. length of spanner

Question 4

whats a force couple ?

Answer 4

pair of forces which are equal in magnitude and opposite in direction.

Question 5

how do you find the resultant of two or more vectors that act in the same direction ?

Answer 5

add them together

Question 6

how do you find the resultant of two or more vectors that act in opposite directions ?

Answer 6

minus ( calculating the difference )

Question 7

what does both scalar and vector quantities have ?

Answer 7

magnitude

Question 8

does scalar quantities have direction ?

Answer 8

no, but vector does

Question 9

whats the calculation for stress ?

Answer 9

force / area

Question 10

whats the calculation for strain ?

Answer 10

change in length / original length

Question 11

what is plasticity ?

Answer 11

materials ability to change its shape permanently when subjected to stress.

Question 12

what does hookes law state ?

Answer 12

extension of an elastic object is directly proportional to the force applied to it.

Question 13

whats the equation for young modulus ?

Answer 13

stress / strain

Question 14

whats hardness ?

Answer 14

tendency to resist indentation

Question 15

whats strength ?

Answer 15

tendency to withstand an applied load without failure.

Question 16

whats toughness ?

Answer 16

tendency to resist breakage when deforming or when impact forces are applied to a material.

Question 17

whats brittleness ?

Answer 17

tendency to break without change of shape

Question 18

whats malleability ?

Answer 18

tendency to undergo compressive stress without damage

Question 19

what is ductility ?

Answer 19

tendency to undergo tensile stress without damage.

Question 20

whats a flash point ?

Answer 20

temperature at which a combustible liquid will catch fire when exposed but a naked flame.

Question 21

whats a inert substance ?

Answer 21

substance that will not chemically combine with another substance.
( all inert substances are gasses )

Question 22

whats the atmospheric pressure at sea level ?

Answer 22

14.7 psi

Question 23

whats atmospheric pressure measured with ?

Answer 23

mercury barometer

Question 24

whats ambient pressure ?

Answer 24

pressure in the area immediately surrounding an object.

Question 25

explain buoyant force ?

Answer 25

body in fluid will be subject to a upward force equal to the weight of fluid displaced.

Question 26

how does a hot air balloon rise ?

Answer 26

heated air filled into balloon is less dense than air displaced