energy & nuclear science1 nuclear technology energy - the driving force of change natural units...

Energy & Nuclear Science 1

Nuclear Technology

Energy - the driving force of change Natural Units - atoms, molecules, moles, and electrons Atoms - the tiny wonders Atomic Nuclei - small frontier to explore Radioactive Decay - transmutation of nuclides Particles - frozen energy states Nuclides - composite particles of nucleons Nuclear Reactions - changing the hearts of atoms Nuclear Fission - energy for war and peace Nuclear Fusion - an ideal energy source Ionizing Radiation - radiation detection and measurements Radiation Safety - safety in nuclear technology Nuclear Technology - applications of nuclear technology


Energy & Nuclear ScienceThe most important aspect of nuclear technology is the large amount of energy involved in nuclear changes, radioactivity, nuclear reactions, radiation effects etc.

Thus, the energy concept is very important before we start to explore nuclear science.

Nuclear energy associates with mass according to Einstein’s formula,

E = m c 2

but what does it mean?

E = m c2


Energy – driving force of changeChange is the only constant in the universe.

Changes: winds, rains, storms, thunders, forest fires, earthquakes, waves, plant growth, food decay, ocean tides, formation and melting of ice, combustion, and growing old ... more example please.

What are physical and non-physical changes?

What causes changes?Heatelasticitygravityelectromagnetic wave

…

Identify changes and energy in everyday events


Recognizing energy

Energy plays an important partAnd it’s used in all this work;Energy, yest energy with power so great,A kind that cannot shirk.

If the farmer had not this energy,He would be at a loss,But it’s sad to think, this energyBelongs to a little brown horse.

A school verse by Richard Feynman Nobel laureate for physics

Photo of Feynman and Murray Gell-Men


Mechanical Work

Mass: m kg

Acceleration: a m s-2

Force: F = m a N (Newton = kg m s-2)

Distance: s m

Work: W = F • s J (N m or kg m2 s-2)

Potential energy Wp = m g h unites?

Kinetic energy Wk = ½ m v 2 work out unites

0.1 kg

1 N

Think and deal with quantity of energy


Properties of PE and KE

PE and KE are state functions – depending on only the final conditions not on how the conditions were arrived (path).

Changes of PE and KE depend on only the initial and final conditions, not on the paths.

PE and KE are inter-convertible, but not destroyed.

Do you know any other properties?

Energy in amusement parks

Explain state functions


The Temperature ConceptObjective comparison of energy flow potentials – temperature scales.

0th law of thermodynamicsTwo bodies each equal in temperature to a third body are equal in temperature to each other. Maxwell (19th century)

Temperature scales led to the concept of heat

The science of heat - thermodynamics.

N F C K

2 1 2 1 0 0 3 7 3 .1 5

1 2 9 8 3 7 3 1 0

0 3 2 0 2 7 3 .1 5

-4 0 -4 0 2 3 3 .1 5

N ew ton (N ), F a h r en h e it (F ) , C e ls iu s ( C ) , a n dK elv in (K ) tem p er a tu r e sca les .


Hot, Cold and Heat

Temperatures (hot and cold) indicate potential for heat flow.

They are intensive properties as are color, electrical potentials, concentrations heat capacity, pressures, etc.

Temperature scales made hot-cold measurements quantitative, but they are not quantities to be added or subtracted.

Heat, transfers from object to object, elusive. When heat is transferred between objects, their temperatures change.

Heat is an extensive property as are electric charge, length, mechanical work, mass, mole, time, etc.

Heat is measurable in quantities, units being btu, cal, kcal, J, kJ, kwh, etc.An amount of heat required to raise the temperature of 1.00 g of water from 288.5 to 289.5 K is defined as 1.00 calorie or 4.184 J.

What are the differences between hot-cold temperature and heat?

Differentiate temperature from heat


The Concept of Heat

Heat is evidently not passive; it is an expansive fluid which dilates in consequence of the repulsion subsisting among its own particles

Joseph Black (1728-1799)

- is a typical additive quantity

- is different from hot

- inter-convertible to mechanical work (same units)

Is heat a fluid like water?


The Energy Concept

T h e r m o m e t e r

m g h

Jo u le s e x p e r im e n t d e m o n s t r a t e d t h eg e n e ra t io n o f h e a t b y m e c h a n ic a l m e a n s .

Inter-conversion- discovered unexpectedlyby Ben Thompson (1753-1814) while making cannons.

Conversion factor was determined by J. Joule (1818-1889) 1 cal = 4.184 J

This entity was called effort, living force, and travail, before the term energy was coined by Thomas Young (1773-1829)

Inter-conversion of Heat and Work

Joule in his 20s


Energy

Heat and work are really energy being transferred.

Energy stored in a body is neither heat nor work.Kinetic energies of gases are proportional to their temperature. Once absorbed, the nature of heat has changed.

Motion of gas molecules gave rise to pressure - Daniel Bernoulli (1700-1782).

Rudolf J.E. Clausius (1822-1888), James Clerk Maxwell (1831-1879), W. Thomson, and Ludwig E. Boltzmann (1844-1906), studied the relationship between temperature and energy of molecular motion. Many elegant theories have been developed as a result.


Forms of EnergyHeatMechanical work Waves (sound etc)

Electromagnetic radiation (waves)Electrical (charge transfer)ChemicalMass (nuclear)

Other driving forces

Benefitchi

determinationencouragement

inspirationlovelaw

motivationresolutionscarcity

What are the properties of energy in these forms and how to evaluate them?


Electric Energy

+++++++

-------

Electric fieldElectric field

Gravitational field

Electric energy, E Joule

potential, V Volt

charge, q Coulomb

E = V qE = hg m

1 J = 1 CV = 1 N m etc

Be able to evaluate quantities of electric energy


Simple electric energy calculations

Potential difference, V, current i ( = q / t ) and resistance R.

V = i R (Ohm’s law)

Power P, (I/o)P = V q / t = V i ( i = current ) = R i 2 (Joules law)

Energy and powerE = P t ( unit kilo-watt-hour)

DC and AC

Electric energy, E Joulepotential, V Voltcharge, q Coulomb

E = V qE = hg m

1 J = 1 CV = 1 N m etc


eV – a special energy unit

Electron-volt, eV, is a very special energy unit, although we have not discussed electricity and electrons yet.

Charge of an electron = 1.6022e-19 C (one of the fundamental physical constants).

The energy required to increase the electric potential of an electron by 1 V is 1 eV = 1.6022e-19 J (J = C V).

Other units used in nuclear energy arekeV (1000 eV)MeV (1e6 eV)GeV (1e9 eV)

Be able to inter-convert energy quantities in various units


What is light?Wave properties? Particle properties?

MasslessInterferenceNewton ringdiffraction

Law of reflection law of refraction

move in straight line??


Electromagnetic Radiation

Electromagnetic radiation is transfer of energy by EM waves via no medium(?).

EM waves travel in empty space at constant speed (c = 2.997925e8 m/s constant).

EM waves are characterized by wavelength (or frequency )

Light is part of the EM spectrum.

EM radiation has a very wide spectrum ( or ).


The EM Spectrum

Long-wave RadioBroadcast radio band

Short wavelength radioInfrared

VISIBLEUltraviolet

X-raysGamma rays

The EM Radiation Spectrum

> 600 m 600 - 200 m200 m - 0.1 mm0.1 - 0.0007 mm0.7 - 0.4 um0.4 um - 1 nm1 nm - 0.1 pm0.1 nm

Remember the order of these regions


The EM Wave Spectrum


The Visible Spectrum

A color pattern seen in an oil filmDouble rainbow

http://search.gallery.yahoo.com/search/corbis_id?p=cid%3A11491320


Photons, E = h

Max Planck assumption, E = h , was shown to be true by Einstein’s photoelectric experiment.

Speed of light, c = 3e8 m s-1

wavelength, frequency of light, = c / Planck constant, h = 6.62619e-34 J senergy of a photon E = h .

A photon is a bundle of energy, and it’s like a particle of light.

Use wave to show and .

Max Planck(1858-1947)Nobel Prize (1918)

http://www.britannica.com/needmore


The Photon StoryMax Planck assumption, E = h, was shown to be true by Einstein’s photoelectric experiment.

Frequency

INTENSITY

Wien’s Law

Rayleigh’sPrediction

Experimental curveand Planck’s prediction

Kinetic energyof electron

FrequencyThreshold

Explain the photoelectric effect.


Photon EnergyTypical red light, = 4.69e14 s-1 (Hz),

= c / = 3e8 m s-1 / 4.69e14 s-1 = 640 nm

Wave number = 1 / = 1 / 6.40e11 m = 1.56e6 m-1

E = h = 6.62619e-34 J s * 4.69e14 s-1

= 3.1 x 10‑19 J (1 eV / 1.6 x 10-19 J) = 1.9 eV per photon

find wavelength or frequency of a violet photon and carry out similar evaluations.


LaserLight Amplification by Stimulated Emission of Radiation (LASER)

Greenphotons Stimulated decay,

Red laser

Spontaneous decay

Red laser

Green pumping light

Partial mirrorMirror


Chemical Energyenthalpy

2H2 + O2

2H2O(g)373K

2H2O(l)273K

2H2O(s)273K12 kJ, energy of fusion

81 kJ, energy ofvaporization

484 kJ, energy ofreaction

2H2O(l)373K15 kJ, heat

4H + 2O

1469 kJ, bond energy

Understand these terms on energy or enthalpy

Bond energyenergy of reactionenergy related to temperatureenergy related to states melting, vaporization, phase transitionmass loss in chemical reactions


Relative and Zero Masses

m = m

v

c

o

21 - ( ) Universal speed299,792,458 m/s

Special theory of relativity (by Einstein) shows that mass m of a particle with velocity, v relates to the mass when v = 0, which is called zero mass, mo.


Mass and EnergyEinstein further showed that the relativistic mass, m, of a particle exceeds its rest mass mo (m = m - mo). The increase in kinetic energy E and increase in mass are related by:

E = m c 2

or E = m c 2

Implication:Mass and energy are equivalent. Mass can be expressed in energy unit and vice versa.

241800 J = 241800/c 2 = 2.7 x 10-12 kg = 3 ng


Power – rate of energy transfer

mgh

Power = m g v,v, pulling velocity

The SI unit for power P is watt named after James Watt, 1 watt = 1 J s–1

Work out by heart 1 kilowatt-hour = __ J = __ cal = __ BTU


The law of Conservation of Energy

Energy converts among various forms without any loss or gain.

Energy cannot be created nor destroyed.

Conversions of energy in various forms have definite rates. These rates never change, and we have energy conversion factors.

mgh

Power = m g v,v, pulling velocity

1 amu = (12 kg/k mol)/12

= (1 kg/k mol)/(6.022e26 (k mol)-1)

= 1.661e-27 kg = 931.5 MeV

1 amu = 1/12th of mass of a C12 atom


Some conversion factors1 eV = 1.602 x 10‑19 J1 eV/molecule = 23045 cal/mol1 MeV = 1.602 x 10‑13 J

1 amu = 1.66043 x 10‑31 J= 931.4812 MeV

1 cal = 4.184 J

1 atm L = 101.3 J

1 J = 1 coulomb‑volt

1 joule = 107 ergs

1 BTU = 252 calThese factors are in the lecture notes. Be able to do unit conversion.


Transmitting Energy by Sound

Sound intensity (I, watt/m2), level (SIL) is SIL (dB) = SILo + 10 log (I/Io )

At 1000 Hz, the threshold SILo = 0 dB, I0 = 10-12 watt / m2)

When I = 1 watt / m2 SIL = 120 dB (work out)

Comfortable hearing is between 50 and 70 dB, whereas 10 dB is a bel (after A. G. Bell, 1847-1922). A shock wave is due to a sharp difference in pressure from (nuclear) explosions. Shock waves cause serious injuries to ears, and destroy buildings and structures.


Thermodynamics

Thermodynamics was derived from the Greek words therme (heat) and dynamis (force), intensely studied in the 19th century motivated by the need to convert heat into mechanical work.

0th law: if T of A, TA = T B, TB = TC, then TA = TC

1st law: law of conservation of energy, recognizing internal energy Ein = q – w.

2nd law: not possible for a machine to convert all the heat into work.

3rd law: changes are caused be energy decrease and entropy increase.

These laws govern engineering of energy transfer.


Energy Resources and Utilization

What are possible energy resources?

Solar energy

Geothermal energy

Nuclear energy

??? (class discussion)

What technologies are available to utilize these resources?

???

How efficient are some of the technologies?

???


Energy crisis and social problems

These issues affect us all, and please apply basics and human natures to solve these problems so your generation will live happily hereafter.

Arbitrary Coordinate

Demand

Cost

Level

energy & nuclear science1 nuclear technology energy - the driving force of change natural units...

Documents

energy nuclear science3

energy nuclear science7

energy nuclear science2

nuclear energy associates

work energy

energy concept

yest energy

energy nuclear science8