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No. Terms Definitions Equations

CHAPTER 1&2: PHYSICAL QUANTITIES AND UNITS & MEASUREMENT TECHNIQUES

1. Base Quantities2. Derived Quantities Quantities that are defined in two or more base quantities

3. Principle of

Homogeneity

When the units of all terms in an equations are the same, the

equations is said to be homogeneous

4. Avogadro Constant, NA Number of atoms in 0.012 kg of Carbon-12 NA=6.023x1023

mol-1

n !m

M

n !N

N A

5. Scalar Quantity Physical quantity that has only magnitude Speed, mass, density, pressure

6. Vector Quantity Physical quantity which has magnitude and direction Velocity, acceleration, force, momentum

7. Systematic Error Magnitude is constant in all reading

Cannot be eliminated by taking average

Zero error, reaction time, error due to assumption of physical conditions,

incorrect calibration

8. Random Error Readings to be scattered equally about the actual value Parallax error

9. Accurate Reading Measurement that is close to the actual value

10. Precise Reading Measurement that has very low or no random error

11. Uncertainty Smallest scale division of the instrument if the scale division 1mm

Half the smallest scale division of the scale division >1mm

CHAPTER 3: KINEMATICS

12. Distance Measure of how far an object has moved

13. Displacement The distance moved in a particular direction

14. Speed Distance moved per unit time

15. Velocity Rate of change of displacementAverage velocity =

( s(t

Instantaneous velocity =

dv

d t

16. Acceleration Rate of change of velocity Average acc =

v

t

Instantaneous acc =

d v

d t

17. Equations of Motion *For constant acceleration

v ! u at

s !1

2u v t

s ! ut 1

2at 2

v 2! u2

a s

e



18. Weight Gravitational force on body

W ! mg

*Acceleration due to gravity =

F

m

!m g

m

! g

*Unit for g: ms-1 or Nkg

-1

19. Force

Impulse

Rate of change of momentumForce,

F !m v u

t

Impulse,

F t !m v u

t

20. Projectile Motion

**

T ! t R

! 2t H

y

u x ! u cosU and

u y ! u sinU hence

y

a x ! 0and

a y ! g y Max R when

y Velocity at an instant (

v ! u at )

v x ! u cosU 0

v y

! u sinU g t

y Displacement at an instant (

s ! ut 1

2at 2 )

s x ! u cosU t 0

s y ! u sinU t 1

2 g t 2

y Hence, maximum height, H (

v 2! u2

a s&

v yH

! 0 )

02

! u sinU 2

2 g H

H !1

2

u sinU 2

g

y Time to reach H (

v ! u at &

v yH

! 0 )

0 ! u sinU g t

t H

!u sinU

g

y @t to fall back to the ground(

t R

! 2t H

!2u sinU

g) or (

s ! ut 1

2at 2)

0 ! u sinU T 1

2 g T 2

T !2u sinU

g

U ! 45r



y Max

s x /range,

R (

s ! ut 1

2at 2 but use

T ! t R ! 2t H )

R ! u cosU T 0

*Sub

T !2u sinU

g

R !u2 sin 2U

g

CHAPTER 4: DYNAMICS

21. Newtons First Law of

Motion

Every body continues in its state of rest or of uniform motion in a

straight line unless acted on by external forces to change that state

*Dynamic Equilibrium: A moving object experiencing zero net

force

*Static Equilibrium: An object at rest

y Inertia: Property of a body which resists change in motion or its

state of rest *depends on mass

y Mass: Property of a body which resists change in motion

y Gravitational field: Region where a mass experiences gravitational

force

y Gravitational field strength, g: Force per unit mass acting at that

point

y Linear momentum, p: Product of mass and velocity of an object

g ! F

m

p ! mv

22. Newtons Second Law of Motion

The rate of change of change of momentum of an object isproportional to the resultant force acting on it, & change in

momentum takes place in the direction of that force

F wd mv d t

F wma

F ! k ma

23. Newtons Third Law of

Motion

When body A exerts a force on body B, body B exerts a force equal on

magnitude but opposite in direction on A. The force is of the same

type.

*Characteristics of the A=R

y Act on different body

y Are of the same type of forcey Act at the same time

y Have the same magnitude but opposite direction

y Act along the same line of action

Action=Reaction

24. Principle of

Conservation of

Momentum

The total linear momentum of a system of forces is constant if no

external force act on the system

y Elastic collision

7 Ek conserved

y Inelastic collision

7 Ek not conserved*E lost as heat/ sound

y Inelastic *note the direction of

u1

,

u2

m1u1

m2u2

! m1v1

m2v2

y Elastic

m1u1

m2u2

! m1

m2 v

y Explosion

m1u1

m2u2

! 0

m1v1

! m2v2



y Explosion

25. Newtons Law of

Restitution

When two objects moving in same direction collide,

Relative v of approach= Relative v of separation y Relative v after = -e (relative v before)

v1 v2 ! e u1 u2

CHAPTER 5: FORCES

26. Fundamental Forces y Strong nuclear force

y Weak nuclear force

y Electromagnetic force

y Gravitational force

*Force also: product of the rate of change of mass and the change in

velocity

27. Couple A pair of equal and opposite forces which are parallel and whose line

of action do not coincide28. Moment of Forces

(about a point)

The product of the force and the perpendicular distance from the line

of action the force to the point

*F, take the magnitude, no need to x2

29. Torque Product of magnitude of a turning force and the perpendicular

distance of the line of action from an axis of rotation

*A specific type of moment

30. Principle of Moments For a system in equilibrium, the sum of moments of all forces acting

on the system about any point is zero

y Equilibrium: 7 F =0 and 7 Torque=031. Centre of Mass (of an

object/system)

The point at which an applied force acting at it produces acceleration

in the direction of the force but causes no rotational motion

32. Centre of Gravity The point where the weight appears to act

CHAPTER 6: WORK, ENERGY, POWER

33. Work, W Product of force and the displacement in the direction of the force

y 1J= Work done by 1N force as it acts through a distance 1m

along the line of force

W against gravityW =mgh

W by moving vehicle W =Ds *D=driving F

W due to expansion of gas where

34. Energy,E Capacity of doing work

*J or kWh

35. Kinetic Energy, Ek Energy possessed by a body due to its motion

36. Gravitational Potential

Energy, Ep

Energy possessed b an object due to its position in a gravitational

field/vertical ha=eight above the Earths surface

37. Electric Potential Energy (Of a charge Q at a point of p.d. V in an electric field )

38. Elastic Potential Energy Energy stored in a body due to deformation (stretching/compressing) From i.e. Hookes Law and F-e graph:

Moment ! F v Bd

W ! F s

W ! p v f vi

p !

F

A

E k

!1

2mv

2

E p

! m gh

E ! QV

F ! k e



W=¡

ve F x e

39. I¢

£

e¤ ¢ ¡

l E¢

e¤ ¥

y ¦ U S§ ̈

of all the ki¢

etic e¢

e¤ ¥

y and potential ene¤ ¥

y of the ato ̈

s and

molec§

les of a matte¤

y The Ep: Total ene©

y re

ired to maintain the position of

particles against i/m forces of both attraction and repulsion

in the matter

y The Ek: The average bulk energy of the vibrational

translational and rotational energies of all the particles in the matter

40. Principle of Conservation

of Energy

The total energy in a closed system is al

ays constant, or

Energy can neither be created nor destroyed but can be transferred

f rom one form to another

41. Po

er, P Rate at which work is being done Mechanical power against F resulting in v,

Electrical power dissipated when current I flow with p.d. v in a device

* Unit for P: W

*Energy Loss

Energy consumed by/lost in a device at p.d. v when Q charge pass

through

W=QV=Ivt

42. Efficiency

CHAPTER 9: PHASES

F MATTER

43. Kinetic Theory of Matter y Matter is made up of tiny discrete particles

y Particles are continuously in motion

44. Kinetic Theory of Gases y All molecules behave as identical, hard, perfectly elastic spheres

y Vol of molecules negligible compared to vol of gas

y Molecules move f reely in random motion

y Intermolecular forces are negligible y Time of collision is negligible compared to time between collision

W !1

2 F v e !

1

2k v e2 !

1

2 EA

e2

l

¨

ª©

¸

º¹

W

1

2

F

A

¨ª©

¸ º¹ A

¨ª©

¸ º¹

U ! E E p

P !!

t !

"

s

t !

"

v

P ! IV ! I 2 R ! V 2

R

Useful energy output

Total energy outputv100%

Useful power outputTotal energy output v100%

Area under ra h



45. Molecular Structure S L G

Spacing Closely,

regularlypacked

Slightly

further apart

Very far apart

Ordering Long-ranged

order spread

across a

lattice-space

Short-ranged

order

No order

Vol, shape F, F F, N N, N

Inter-atomic distance of S and L = 3v10-10

m

Inter-atomic distance of G = 33v10-10

m

46. Kinetic Model S L G

Motion

of

molec

Vibrate about

its mean

position

Random and

translational

motion

Translate

throughout

space at high

speed

I/m F High Attractive F,

cohesive F

Attractive F,

repulsive F

negligible

47. Density Mass per unit volume of a material*Unit for density: kg m

-3

48. Solids y Crystalline (metals, NaCl

compact regularly structured unit cellsionic/metallic

y Non-crystalline

Amorphous (glass

irregular atomic structures

weak Van der Waals

Polymeric (rubber, cellulose, proteins; plastic, polythene,

perspex)

large organic molecules arranged in disorderly manner

y Polycrystalline

Materials are made up of grains that are of many tiny crystalsograin size, softer the material/ q melting temp

y Non-crystalline

Amorphous: transparent - less compact structures, disorderly

arrangement of atoms

Polymeric: low strength and melting temp Van der Waals

tough - flexible structures

49. Pressure, P Average force acting normally per unit area

Depends on:

y No of molec per unit volume

y Speed of molec

y Frequency of collision

*scalar quantity *Unit of pressure=Nm-2

=Pa

50. Pressure in Liquids Force per unit area that is acting perpendicular to surface area

concerned where

*760 mm Hg=13600 x 9.8 x 0.76=1.013 x 105

Pa at 0rC

51. Pressure in Gases Pressure due to the force acting on the walls by the molecules of gasThe average rate of change momentum of the molecules

V !m

v

p !F

A

p ! V gh

V !m

v



CHAPTER 10: DEFORMATION OF SOLIDS

52. Deformation The change in shape caused by external forces.

-compressive

-tensile

53. Hookes Law The extension or compression e of a material by a constant load F is

directly proportional to the load applied provided the proportional

limit is not exceeded

F =ke

*Spring constant: Force per unit extension

y Parallel spring:

y Series spring:

54. Compressive strength The load or force applied per unit area on the material (under

compression)

55. Tensile strength The tensile stress is the load applied per unit extension resulted

(under extension)

56. Tensile Stress, W Force applied per unit cross-sectional area of the wire that is normal

to the direction of force

Results in a tensile strain set up within the wire

*Like pressure

*A=Area of wire=

57. Tensile Strain, I The extension e per unit length l of the wire

58. Youngs Modulus, E The ratio of tensile stress to the tensile strain is a constant for a

material provided the proportionality is not exceeded

***R/ship w k

k depends on:

-E, nature of material

-A & l, geometry & dimension of wire

where F=ke

*Unit for youngs Modulus, E = Pa

59. Elastic Strain Energy, W Work done in stretching the material

Equal to stored in the wire

*Stiff material: Material that resists deformation and requires a large

force to produce a small deformation

From F-e graph, A under curve = elastic strain energy, W

W= =

W= =

From F-e graph, gradient

k !F

e

§k ! k 1

k 2

1

§ k !

1

k 1

1

k 2

a

W !F

A

T d 2

4

I !e

l S

k !E A

l

@

E !W I

!Fl S

Ae

F !A E

l S

¨

ª©

¸

º¹e

k ! A E

l S

potential energy

elastic strain energy

1

2 F e

E Ae2

2l

1

2vF

Av A v

e

l

v l

1

2v str e ssv str ain v vol ume



Gradient = =spring constant,k

From stress-strain graph, A under curve= where

=

= = = strain energy per unit Vol

From stress-strain graph, gradient, m

Gradient = = E

60. Proportional limit Maximum point below which the extension of the wire is proportional

to the applied force

61. Elastic Limit Maximum point below which the wire can return to its original length

when the applied force is removed

62. Yield point Point at which the wore starts to exhibit plastic deformation

CHAPTER 15:WAVES

63. Progressive waves A disturbance that transfers energy outwards as a result of vibrations

of the particles of the medium

Transverse

Longitudinal

-Sound: 340ms-1

in air

Mechanical

Electromagnetic

-have same v in vacuum: = 3 x 108ms

-1

64. Stationary waves Waves where their wave profile do not move through the media of

vibration and the energy is localised

*The superposition of two wave trains with same

y Velocity

y Frequency

y Amplitude but in opposite direction

65. Displacement, x/y Distance of an oscillating particle from its mean equilibrium position

66. Amplitude, a Magnitude of the maximum displacement

67. Period, T Time taken for one complete oscillationwhere

68. Frequency, f Number of oscillations completed in one second*Unit of frequency: Hz

69. Wavelength, P Distance between two successive vibrating particles which are in the

same phase

70. Wave front A line/surface joining all the particles that have the same phase

#

F

( x

1

2W I

1

2W I

1

2vF

Ave

l S

1

Al S

1

2 F e

¨

ª©

¸

º¹

ener g y

vol ume

str e ss

str ain

c ! f P

[ !P

T !2T T

T !2T [

[ ! 2T f

f !1

T



71. Wave velocity, v Velocity of advance of the wave fronts

72.Particle velocity, /

Instantaneous velocity of a particle in the wave

73. Phase difference, The fraction of a cycle that two oscillating particles are out of step *Same phase = same direction, same displacement

74. Phase lag,=

y

If distance is away,

=T

y If distance is 2cm away, P=5cm

=

75. Wave intensity, I Amount of energy passing normally through unit area per unit time

y Intensity received at a point

The power P of the wave crossing the point per unitperpendicular cross-sectional area A

y

*r

2

=distance away from point source

y Intensity received at a pt

*P=power radiated by source

*A=area of spherical Wavefront

Power P radiated from source,

= =

76. Principle of

SuperpositionWhen two waves meet each other at a point, the resultantdisplacement is the sum of the separate displacements

77. Polarization of waves The process of confining the vibrations in one direction normal to the

direction of energy propagation

*Polaroid filter: Allows vibration only in one particular plane to pass through

CHAPTER 16: SUPERPOSITION

78. Coherent Constant phase difference

Same frequency

For better observation,

=a

79. Interference Superposition of two or more wave trains from coherent sources,

causing change in overall intensity

*Conditions: same type of wave, meet at a point, same direction of polarization

Const. Destr.

Path diff

v !P

T !

1

T

¨

ª© ¸

º¹P ! f P

dxd t

dy

d t

(N

N

N !2T

P x

k x

1

2P

N !2T

P

P

2

¨

ª© ¸

º¹

N !2T

5

4

5T

I w a2

I !

1

r 2

I !P

A!

P

4T r 2

@

I r 1v 4T r

1

2

I r 2v 4T r

2

2

I r 1

I r 2

!r 2

2

r 1

2

I r

!1

r 2

nP

2n 1 d

2



*x greater when: sources are close,far from source, high P

*x=separation of int.*

Phase diff

80. Diffraction The spreading of wave fronts through a narrow slit/opening/obstacle

by the superposition of secondary waves from the emerging wave

front

*a=size of aperture

For better observation,

a of the same order as the P

If a<P, diffraction more appreciable

81. Diffraction Grating Plate on which there is a large number of parallel, identical and veryclosely-spaced slits Spacing between slits, d=

82. Fundamental Frequency Lowest resonant frequency of vibration *Overtones have f which are integral multiples of it

CHAPTER 17: ELECTRIC FIELDS

83. Electric Field A region where a charge experiences electrostatic force Lines show direction of positive particles motion

84. Electric Field Strength, E The force per unit positive charge on a small test charge*Unit of E: NC

-1

where d=separation of plates *Unit of E: Vm-1

E= -potential gradient =

E due to point charges:

85. Electric Current, I Rate of flow of charged particles

*e-flow :-ve to +ve but conventional flow: +ve to -ve

*1C= the amount of charge that passes a point in a circuit when 1Acurrent flows for 1s.

(Instantaneous)

(Average)

86. Electric Potential, VE (at a

pt)

The work done in bringing the unit positive charge from infinity to the

point in a given electric field E

V E !W

q

CHAPTER 19: CURRENT OF ELECTRICITY

87. Potential

Difference,V(between 2

pt in E)

The work done in taking 1C of positive charge from A to B / Energy

transferred from electrical to other forms per unit charge

* 1V= p.d. between two points in a circuit if 1J of energy is transferred

when 1C of +ve charge pass from one point to another against thedirection of the electric field

W ! QV

W

! V I t

! I R I t

! V V

Rt

P !ax

D

sinU !P

a

asinU ! nP

1

N mm

E ! F

q

E !V

d

dv

dx

E ! F

q!

Q

4TI S r

2

I !d Q

d t

I ! Qt

2nT

2n 1 T



V !W

Q!P t

I t !P

I

Hence

P ! W t

* Unit: JC-1

or V

88. Energy and Power

liberated

y Energy dissipated /liberated by device, W

y Power of ea device i.e. energy liberated per second, P

* If its a passive resistor, all P dissipated as heat

W ! QV

!V I t

P !W

t

!QV

t

!I t V

t

! I V

*

P ! I 2 R

!V 2

Rtherefore

H ! I vt ! I 2 Rt !

V 2

Rt

89. Resistance, R (of a

conductor)

Ratio of the p.d. across it to the current passing through it

R !

V

I

*Unit: ;

90. Ohms Law Under constant physical conditions, the ratio of the p.d. across a

conductor to the current flowing through it is a constant

V

I ! constant

91. Resistivity, V (of a

material)

Numerically equal to the resistance of a sample of the material of unit

length and unit cross-sectional area

R !Vl A

*Unit for resistivity: ;m

92. Electromotive Force,

e.m.f. , E(of a source)

The energy transferred from other forms to electrical energy by it in

driving unit charge round a complete circuit / Ratio of power it generates to the current it delivers

y Terminal p.d. p.d. between the terminals of a cell when a

current is being delivered

E

!

W

Q / E=

!

P

I

93. Internal resistance, r (of

a cell)

Resistance due to the cells chemical constituents against the flow of

current

E=V+v = V+Ir = IR+Ir = I(R+r)

CHAPTER 20: D.C. CIRCUIT

94. Kirchoffs First Law In a network of circuits, the total current flowing into a junction is

equal to the total current flowing out of it

7 I in ! 7 I out

95. Kirchoffs Second Law Around a closed loop in a network of circuits, sum of e.m.f. is equal tosum of p.d.

(Applies conservation of energy)

7 E ! 7V

7 E ! 7 I R

96. Series

R ! R1

R2

R3

97. Parallel

1

R!

1

R1

!1

R2

!1

R3

I ! I 1

I 2

98. Potential Divider A circuit that divides the sources V into a number of p.d. across

various sections in the circuit

From 51,

V 1

! I R1and

V 2

! I R2



V 1

!V

2

R2

¨

ª©

¸

º¹ R1

aV 1

V 2

!R1

R2

99. Potentiometer A circuit that is primarily used to measure p.d.

Used to

y Measure internal resistance, very small e.m.f. (thermocouple),

ammeter (and calibrate it)

y Measure and compare e.m.f.s, resistances

V w L

V 1

V 2

!L1

L2

CHAPTER 27: NUCLEAR PHYSICS

100. Atom Made up of a nucleus of positively-charged particles and uncharged

neutrons surrounded by negatively-charged electrons revolving in the

space around the nucleus

y d of nucleus= 10-15

m

y d of atom = 10-15

m

y charge of e-=1.6 x 10

-19C

y 1 atomic mass unit,u =

1

12mass of a C-12 atom =1.66x10

-27kg

101. Nucleon/Mass Number,

A

Total number of protons and neutrons in the nucleus in an atom

102. Proton/Atomic Number,

Z

Number of protons in the nucleus of an atom

103. Isotope Elements that have same proton number but different nucleon

number

104. Relative Atomic Mass, Ar

105. Mass-Energy

Conservation

Sum of the mass and energy of a closed system in similar units are

conserved

(mwill be accompanied by

( E

( E ! (mc 2where c= speed of light

106. Radioactive Decay The spontaneous and random emission of either E, F, or K

y E: He nucleus

2

4 H e

2

y F: [ F-, electron& F

+,positron] y

Z

A X p

Z 2

A 2Y

2

4 H e

2

y

0

1np

1

1 H 1

0e (electron) &

1

1 H p

0

1n

1

0e (positron)

107. Background Radiation Radiation due to surroundings and cosmic radiation entering the

Earths atmosphere108. Half-life The time taken for half the initial number of atoms to disintegrate

PHY DEF half-updted

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