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  1. page IB DP Atomic and Nuclear physics edited ... • Aim 8: the use of radioactive materials poses environmental dangers that must be addressed a…
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    • Aim 8: the use of radioactive materials poses environmental dangers that must be addressed at all stages of research
    • Aim 9: the use of radioactive materials requires the development of safe experimental practices and methods for handling radioactive materials
    [[media type=youtube key=EOHYT5q5lhQ width=560 height=315 width="560" height="315"]]
    What Does An Atom REALLY Look Like? {https://yt3.ggpht.com/-8gtjXJPxH7o/AAAAAAAAAAI/AAAAAAAAAAA/5ytj_6r0PxA/s88-c-k-no-mo-rj-c0xffffff/photo.jpg} The Science Asylum Published on 12 Jul 2017
    Nucleus are 100,000 times smaller than the size of the atoms. The negatively charged electrons in atoms can exist at only well defined discrete energy levels (quantized steps) and they cannot exist in between the levels(Bohr). When I heat Hydrogen gas, the electron in an hydrogen atom can jump from low energy states to high energy states. When electrons do so, they can leave empty energy states but later on they fall back to occupy the energy states again. When electrons fall from higher energy states to low energy states, light energy releases and we can see the discrete emission spectrum (discrete frequencies/wavelenths).
    ...
    Decay: 1. a spontaneous transformation of an elementary particle into two or more different particles 2. of an excited atom or molecule, losing energy by the spontaneous emission of photons
    Radioactive decay: The spontaneous transformation of an unstable atomic nucleus into a lighter one, in which radiation is released in the form of alpha particles, beta particles, gamma rays, and other particles. The rate of decay of radioactive substances such as carbon 14 or uranium is measured in terms of their half-life.
    Array
    Array
    media type=custom key=29391241
    media type=custom key=29391237

    Alpha decay from phet.colorado.edu
    Beta decay from phet colorade.edu
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    Half lives of various elements from no-nukes.org
    Task: Simulate decay by rolling dice and to estimate the decay constant and half-life from the decay curve.
    Aim: To simulate decay by rolling die and to estimate the decay constant and half-life from the decay curve. Apparatus: 100 six sided die.
    Instructions:
    Count and record the total number of die. Each dice must have the same number of sides (for our experiment we will use six-sided dice.)
    Roll all the die at the same time onto a level table. A plastic container can be used to hold all the dice so they can be easily rolled simultaneously. The table should have some friction so that the dice don't slide off the edge. If some of the dice stack up, gently nudge the table so they all lay down flat on the surface.
    Remove all the dice which turn up "1".
    Count and record the number removed.
    Repeat the experiment with the remaining die.
    Record the time interval between each roll as one second and continue the experiment until no dice
    remain from the original batch.
    Plot the decay curves using total number of dice (as a function of time) as well as the activity of the
    sample (as a function of time).
    Estimate the decay constant and half-life from the sample.
    Repeat steps 2-8 except remove all the dice which turn up "1" or "2".
    Interpret the value of the decay constant you find from the graphs, is it what you could have expected?
    Include your graphs and data tables along with your report.
    Reference:
    Giancoli, 6th Edition Physics
    Assessment Criteria:
    Time: 1.0 hrs.
    Due Dates: 13th December 2013

    dN/dt = - λN
    where λ = decay constant (ln 2 / t1/2)
    ...
    • Binding energy may be defined in terms of energy required to completely separate the nucleons or the energy released when a nucleus is formed from its nucleons
    Data booklet reference:
    dED E = Dmc2D mc2
    Aims:
    • Aim 5: some of the issues raised by the use of nuclear power transcend national boundaries and require the collaboration of scientists from many different nations
    • Aim 8: the development of nuclear power and nuclear weapons raises very serious moral and ethical questions: who should be allowed to possess nuclear power and nuclear weapons and who should make these decisions? There also serious environmental issues associated with the nuclear waste of nuclear power plants.
    Nuclear fission
    Click to Run

    7.3 – The structure of matter
    Nature of science:
    (view changes)
    10:38 am
  2. page IB DP Atomic and Nuclear physics edited ... Decay: 1. a spontaneous transformation of an elementary particle into two or more different pa…
    ...
    Decay: 1. a spontaneous transformation of an elementary particle into two or more different particles 2. of an excited atom or molecule, losing energy by the spontaneous emission of photons
    Radioactive decay: The spontaneous transformation of an unstable atomic nucleus into a lighter one, in which radiation is released in the form of alpha particles, beta particles, gamma rays, and other particles. The rate of decay of radioactive substances such as carbon 14 or uranium is measured in terms of their half-life.
    Array
    Array
    Alpha decay from phet.colorado.edu
    Beta decay from phet colorade.edu

    {nuclear decay.PNG}
    Nuclear equations from BBC GCSE Bitesize
    (view changes)
    10:36 am
  3. page IB DP Atomic and Nuclear physics edited ... Decay: 1. a spontaneous transformation of an elementary particle into two or more different pa…
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    Decay: 1. a spontaneous transformation of an elementary particle into two or more different particles 2. of an excited atom or molecule, losing energy by the spontaneous emission of photons
    Radioactive decay: The spontaneous transformation of an unstable atomic nucleus into a lighter one, in which radiation is released in the form of alpha particles, beta particles, gamma rays, and other particles. The rate of decay of radioactive substances such as carbon 14 or uranium is measured in terms of their half-life.
    {nuclear decay.PNG} nuclear decay.PNG
    Nuclear equations from BBC GCSE Bitesize
    Uranium 238 decay chain from www.unitednuclear.com
    ...
    Half lives of various elements from no-nukes.org
    Task: Simulate decay by rolling dice and to estimate the decay constant and half-life from the decay curve.
    dN/dt = - λN
    where λ = decay constant (ln 2 / t1/2)
    the number of nuclei present, N,

    Essential idea: Energy can be released in nuclear decays and reactions as a result of the relationship between mass and energy.
    7.2 – Nuclear reactions
    (view changes)
    10:29 am
  4. page IB DP Atomic and Nuclear physics edited ... Strong Nuclear Force Weak Nuclear Force 1)Gravity 2)Electromagnetic 3)Strong Nuclear Forc…
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    Strong Nuclear Force
    Weak Nuclear Force
    1)Gravity
    2)Electromagnetic
    3)Strong Nuclear Force (SNF)
    4)Weak Nuclear Force (WNF)
    Radioactivity: The emission of radiation by unstable atomic nuclei undergoing radioactive decay.
    It is a process in which atoms with unstable nuclei spontaneously decay emitting subatomic particles and energy as they reconfigure into more stable forms.
    Decay: 1. a spontaneous transformation of an elementary particle into two or more different particles 2. of an excited atom or molecule, losing energy by the spontaneous emission of photons
    Radioactive decay: The spontaneous transformation of an unstable atomic nucleus into a lighter one, in which radiation is released in the form of alpha particles, beta particles, gamma rays, and other particles. The rate of decay of radioactive substances such as carbon 14 or uranium is measured in terms of their half-life.
    {nuclear decay.PNG} nuclear decay.PNG
    Nuclear equations from BBC GCSE Bitesize
    Uranium 238 decay chain from www.unitednuclear.com
    Half-life
    The HALF-LIFE of an atom is the time taken for HALF of the radioisotopes in a sample to decay. The decay of radioisotopes can be used to measure the material’s age.
    The half-life of radioisotopes varies from seconds to billions of years. from ndt-ed.org
    {Half life.jpg} Half life.jpg
    Science in Focus Radioactivity S100LS05 Lammas Science Published on 15 Nov 2012
    Half lives of various elements from no-nukes.org
    Task: Simulate decay by rolling dice and to estimate the decay constant and half-life from the decay curve.

    Essential idea: Energy can be released in nuclear decays and reactions as a result of the relationship between mass and energy.
    7.2 – Nuclear reactions
    (view changes)
    10:24 am
  5. page IB DP Atomic and Nuclear physics edited ... l = ( 3 x 10 8 ) / ( 1.45 x 10-15 ) = 207 nm [UV light] Four fundamental forces Gravitation…
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    l = ( 3 x 10 8 ) / ( 1.45 x 10-15 ) = 207 nm [UV light]
    Four fundamental forces
    Gravitational force
    Electromagnetic force
    Strong Nuclear Force
    Weak Nuclear Force

    1)Gravity
    2)Electromagnetic
    (view changes)
    10:19 am
  6. page IB DP Atomic and Nuclear physics edited ... • Aim 9: the use of radioactive materials requires the development of safe experimental practi…
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    • Aim 9: the use of radioactive materials requires the development of safe experimental practices and methods for handling radioactive materials
    What Does An Atom REALLY Look Like? {https://yt3.ggpht.com/-8gtjXJPxH7o/AAAAAAAAAAI/AAAAAAAAAAA/5ytj_6r0PxA/s88-c-k-no-mo-rj-c0xffffff/photo.jpg} The Science Asylum Published on 12 Jul 2017
    ...
    the discrete frequencies/wavelenths of light energy.emission spectrum (discrete frequencies/wavelenths).
    Atomic spectra
    atomic electrons can only exist in certain discrete energy levels.
    ...
    c = f l
    l = ( 3 x 10 8 ) / ( 1.45 x 10-15 ) = 207 nm [UV light]
    Four fundamental forces
    1)Gravity
    2)Electromagnetic
    3)Strong Nuclear Force (SNF)
    4)Weak Nuclear Force (WNF)

    Essential idea: Energy can be released in nuclear decays and reactions as a result of the relationship between mass and energy.
    7.2 – Nuclear reactions
    (view changes)
    10:17 am
  7. page IB DP Atomic and Nuclear physics edited ... • Aim 9: the use of radioactive materials requires the development of safe experimental practi…
    ...
    • Aim 9: the use of radioactive materials requires the development of safe experimental practices and methods for handling radioactive materials
    What Does An Atom REALLY Look Like? {https://yt3.ggpht.com/-8gtjXJPxH7o/AAAAAAAAAAI/AAAAAAAAAAA/5ytj_6r0PxA/s88-c-k-no-mo-rj-c0xffffff/photo.jpg} The Science Asylum Published on 12 Jul 2017
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    energy states, discrete light energy
    ...
    see the spectrumdiscrete frequencies/wavelenths of light
    Atomic spectra
    atomic electrons can only exist in certain discrete energy levels.
    (view changes)
    10:10 am
  8. page IB DP Atomic and Nuclear physics edited ... • Aim 9: the use of radioactive materials requires the development of safe experimental practi…
    ...
    • Aim 9: the use of radioactive materials requires the development of safe experimental practices and methods for handling radioactive materials
    What Does An Atom REALLY Look Like? {https://yt3.ggpht.com/-8gtjXJPxH7o/AAAAAAAAAAI/AAAAAAAAAAA/5ytj_6r0PxA/s88-c-k-no-mo-rj-c0xffffff/photo.jpg} The Science Asylum Published on 12 Jul 2017
    ...
    energy states, discrete light energy
    Atomic spectra
    atomic electrons can only exist in certain discrete energy levels.
    (view changes)
    10:03 am
  9. page IB DP Atomic and Nuclear physics edited ... • Aim 8: the use of radioactive materials poses environmental dangers that must be addressed a…
    ...
    • Aim 8: the use of radioactive materials poses environmental dangers that must be addressed at all stages of research
    • Aim 9: the use of radioactive materials requires the development of safe experimental practices and methods for handling radioactive materials
    Nucleus are 100,000 times smaller than the size of the atoms. The negatively charged electrons exist in only well defined discrete energy levels (quantized steps) around the nucleus(Bohr).
    What Does An Atom REALLY Look Like? {https://yt3.ggpht.com/-8gtjXJPxH7o/AAAAAAAAAAI/AAAAAAAAAAA/5ytj_6r0PxA/s88-c-k-no-mo-rj-c0xffffff/photo.jpg} The Science Asylum Published on 12 Jul 2017
    Nucleus are 100,000 times smaller than the size of the atoms. The negatively charged electrons in atoms can exist at only well defined discrete energy levels (quantized steps) and they cannot exist in between the levels(Bohr). When I heat Hydrogen gas, the electron in an hydrogen atom can jump from low energy states to high energy states. When electrons do so, they can leave empty energy states but later on they fall back to occupy the energy states again. When electrons fall from higher energy states to low energy states, light energy releases and we can see the spectrum of light energy.
    Atomic spectra
    atomic electrons can only exist in certain discrete energy levels.
    (view changes)
    9:52 am
  10. page Unit 2 Thermal Physics edited 2.1 Simple Kinetic Molecular Model of Matter Seeing the Invisible: Schlieren Imaging in SLOW M…

    2.1 Simple Kinetic Molecular Model of Matter
    Seeing the Invisible: Schlieren Imaging in SLOW MOTION Veritasium Published on 15 Jun 2017
    2.1.1 States of matter
    Core
    • State the distinguishing properties of solids, liquids and gases
    Seeing the Invisible: Schlieren Imaging in SLOW MOTION Veritasium Published on 15 Jun 2017
    [[media type=youtube key=OG9aBq3V24Y width=504 height=283 width="504" height="283"]]
    GCSE Physics Revision: Solids, liquids and gases from youtube.com
    (view changes)
    9:32 am

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