0
DR.	
  IFFIC:	
  FIRE!	
  
Hello	
  and	
  welcome	
  to	
  our	
  second	
  lecture.	
  	
  Last	
  :me,	
  we	
  reviewed	
  the	
  four	
  
fundam...
NOT	
  “JIMMY”	
  AT	
  ALL.	
  
“Jimmy,”	
  eh?	
  	
  A	
  likely	
  story.	
  	
  Very	
  well,	
  “Jimmy.”	
  	
  The	...
JIGGLING,	
  Dmitri	
  Alekseyevich.	
  	
  Pure	
  and	
  simple.	
  	
  
Do	
  you	
  mean	
  to	
  say	
  that	
  if	
 ...
And	
  molecules	
  are	
  :ny	
  lile	
  bits	
  of	
  something,	
  is	
  that	
  right?	
  	
  
More	
  or	
  less.	
  ...
It	
  is	
  jiggling	
  already,	
  Dmitri	
  Alekseyevich.	
  	
  It	
  is	
  at	
  room	
  temperature,	
  which	
  requ...
The	
  cells	
  in	
  your	
  body	
  can’t	
  operate	
  correctly	
  when	
  they’re	
  jiggling	
  too	
  fast.	
  	
  ...
For	
  example,	
  fire,	
  indeed.	
  	
  Fire	
  will	
  jiggle	
  you	
  to	
  a	
  crisp	
  
before	
  you	
  can	
  sa...
Fire	
  is	
  actually	
  gas	
  that	
  is	
  jiggling	
  so	
  fast	
  that	
  it	
  glows.	
  	
  
Jiggling	
  can	
  m...
Yes	
  indeed.	
  	
  You	
  see,	
  the	
  jiggling	
  energy	
  that	
  is	
  heat	
  does	
  not	
  stay	
  in	
  one	
...
Also,	
  molecules	
  can	
  reduce	
  their	
  jiggling	
  energy	
  by	
  shoo:ng	
  out	
  a	
  
photon,	
  or	
  absor...
Well,	
  essen:ally	
  it	
  is,	
  although	
  it	
  acts	
  like	
  a	
  wave	
  too,	
  which	
  is	
  
one	
  of	
  th...
But	
  I’m	
  not	
  glowing!	
  	
  Nor	
  is	
  my	
  nonbranded	
  toaster	
  pastry!	
  	
  
Remember,	
  Dmitri	
  Al...
Think	
  of	
  the	
  strings	
  on	
  a	
  guitar.	
  	
  If	
  you	
  play	
  them	
  at	
  one	
  set	
  
of	
  frequen...
Similarly,	
  while	
  photons	
  at	
  one	
  frequency	
  produce	
  a	
  beam	
  of	
  yellow	
  
light,	
  at	
  a	
  ...
They	
  are	
  at	
  the	
  infrared	
  frequency,	
  which	
  is	
  the	
  frequency	
  of	
  most	
  heat-­‐related	
  
...
Fire	
  is	
  made	
  of	
  gas	
  that	
  is	
  so	
  superhot	
  that	
  it	
  is	
  also	
  spiang	
  out	
  photons	
 ...
And	
  when	
  carbon	
  atoms	
  join	
  with	
  oxygen	
  molecules	
  to	
  make	
  carbon	
  dioxide,	
  it	
  creates...
It’s	
  not	
  really	
  jumping.	
  	
  The	
  superhot	
  glowing	
  gas	
  is	
  so	
  hot	
  that	
  if	
  another	
  ...
Correct	
  in	
  every	
  respect.	
  	
  Now	
  let	
  us	
  bombard	
  
your	
  nonbranded	
  toaster	
  pastry	
  with	...
Upcoming SlideShare
Loading in...5
×

Dr. Iffic Lecture 2

338

Published on

FIRE!

Published in: Education, Technology, Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
338
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
1
Comments
0
Likes
0
Embeds 0
No embeds

No notes for slide

Transcript of "Dr. Iffic Lecture 2"

  1. 1. DR.  IFFIC:  FIRE!  
  2. 2. Hello  and  welcome  to  our  second  lecture.    Last  :me,  we  reviewed  the  four   fundamental  forces  of  the  universe  and  sorted  out  the  roman:c  life  of   protons  and  electrons.    Dmitri  Alekseyevich,  what  ques:ons  have  arrived   from  the  clamoring  masses  of  adulatory  knowledge  seekers?   We  have  a  ques:on  from  an  individual   purpor:ng  to  be  named  “Jimmy,”  who  asks,   “Dr.  Iffic,  what  exactly  is  fire?”    
  3. 3. NOT  “JIMMY”  AT  ALL.   “Jimmy,”  eh?    A  likely  story.    Very  well,  “Jimmy.”    The  nature  of  fire  is  not  quite   as  tripped-­‐out  crazy  as  you  may  imagine,  but  in  order  to  understand  fire,  you   must  first  understand  heat.    And  heat,  in  a  word,  is  jiggling.     Jiggling?    
  4. 4. JIGGLING,  Dmitri  Alekseyevich.    Pure  and  simple.     Do  you  mean  to  say  that  if  I  jiggle  this  nonbranded  toaster   pastry,  it  will  become  warm  and  delicious?   Well,  it  is  already  delicious.    But  the  heat  of  the  nonbranded   toaster  pastry  is  not  determined  by  the  jiggling  of  the  en:re   pastry.    It  is  determined  by  the  jiggling  of  each  and  every   individual  molecule  within  the  pastry.    That  is  what  heat  energy  is   –  the  jiggling  of  molecules.    
  5. 5. And  molecules  are  :ny  lile  bits  of  something,  is  that  right?     More  or  less.    Molecules  are  collec:ons  of  atoms  that  are  stuck  together  very  :ghtly   because  of  what  their  electrons  are  doing.    And  molecules  are  always  jiggling  back  and  forth   to  some  degree.    The  jiggling  is  so  small  that  we  can’t  see  it.    But  we  can  sense  it,  and   observe  it,  as  heat.    Hot  molecules  are  jiggling  fast.    Cold  molecules  are  jiggling  slower.     MOLECULE   atom   atom   atom   atom   atom   Cold  =  slow   Hot  =  fast  
  6. 6. It  is  jiggling  already,  Dmitri  Alekseyevich.    It  is  at  room  temperature,  which  requires  a  certain   amount  of  jiggling.    If  you  put  it  in  the  freezer,  it  would  jiggle  slower,  but  there  would  s:ll  be   some  jiggling  going  on.    In  theory,  if  your  pastry  stopped  jiggling  altogether,  it  would  be  at   absolute  zero  temperature  –  but  it’s  impossible  to  stop  all  the  jiggling  in  a  molecule.     Incredible  jiggling   Intense    jiggling   Moderate  jiggling   Very  lile  jiggling   Absolutely  no  jiggling   It’s  strange  to  think  that  my  pastry  will  jiggle  once  I  toast  it.    
  7. 7. The  cells  in  your  body  can’t  operate  correctly  when  they’re  jiggling  too  fast.    And  when   cells  can’t  operate  correctly,  they  die.    So  when  your  nerves  sense  that  the  jiggling  is   geang  to  dangerous  levels,  they  send  a  message  to  your  brain  saying,  HOOLABALOOLA!     GET  YOUR  HAND  OFF  THAT  HOT  THING,  YOU  CELL-­‐KILLING  IMBECILE!    The  fact  that  heat   is  jiggling  doesn’t  mean  it’s  no  big  deal  –  too  much  jiggling,  or  not  enough  jiggling,  is   very  dangerous  for  living  things.     If  heat  is  just  jiggling,  why  does  it  hurt  to  touch  something  hot?    
  8. 8. For  example,  fire,  indeed.    Fire  will  jiggle  you  to  a  crisp   before  you  can  say,  HOOLABALOOLA!    And  what  use   will  your  nonbranded  toaster  pastry  be  to  you  then?     For  example,  fire.    
  9. 9. Fire  is  actually  gas  that  is  jiggling  so  fast  that  it  glows.     Jiggling  can  make  something  glow?     So  what  IS  fire?    
  10. 10. Yes  indeed.    You  see,  the  jiggling  energy  that  is  heat  does  not  stay  in  one   place.    It  has  a  tendency  to  spread  out  as  much  as  possible.    One  way  it   spreads  out  is  when  molecules  touch  each  other.    The  faster-­‐jiggling,  hoer   molecules  transfer  some  of  their  jiggling  energy  to  the  slower-­‐jiggling,   colder  molecules,  un:l  everything  is  jiggling  the  same  amount.     That  makes  sense.    
  11. 11. Also,  molecules  can  reduce  their  jiggling  energy  by  shoo:ng  out  a   photon,  or  absorb  a  photon  and  transform  it  into  jiggling  energy.    
  12. 12. Well,  essen:ally  it  is,  although  it  acts  like  a  wave  too,  which  is   one  of  the  more  tripped-­‐out  crazy  aspects  of  science.       So  super-­‐hot  things  start  shoo:ng  out  photons?     OK,  that’s  a  lile  weird.    Isn’t  a  photon  just  a   :ny  lile  par:cle  of  light?     Not  just  super-­‐hot  things,  Dmitri  Alekseyevich.    You  and  your   nonbranded  toaster  pastry  are  shoo:ng  out  photons  right  now,   and  absorbing  photons  that  got  shot  out  from  other  things.    
  13. 13. But  I’m  not  glowing!    Nor  is  my  nonbranded  toaster  pastry!     Remember,  Dmitri  Alekseyevich,  not  all  photons  are  visible  to  our  eyes.    Radio   waves,  microwaves,  and  gamma  rays  are  all  made  of  photons,  but  we  can’t  see   them,  even  though  we  can  use  them  to  transmit  informa:on,  cook  frozen  burritos,   and  turn  people  into  the  Hulk.    Because  photons  behave  like  waves,  they  have   frequencies,  and  different  frequencies  create  different  forms  of  radia:on.     Radio  Waves   Microwaves   Gamma  Rays  
  14. 14. Think  of  the  strings  on  a  guitar.    If  you  play  them  at  one  set   of  frequencies,  you  get  Mary  Had  a  Lile  Lamb.    
  15. 15. Similarly,  while  photons  at  one  frequency  produce  a  beam  of  yellow   light,  at  a  different  frequency  they  produce  microwaves.     whereas  if  you  play  them  at  another  set  of  frequencies,  you  get  the   latest  hit  by  the  Icelandic  death  metal  band  Sküllmelter.      
  16. 16. They  are  at  the  infrared  frequency,  which  is  the  frequency  of  most  heat-­‐related   photons,  and  which  is  invisible  to  us,  unless  we  are  commandos  with  super  cool   thermal  imaging  goggles.     OK,  so  why  can  we  see  fire?     So  what  frequency  are  the  heat-­‐related  photons  coming  out  of  me  and  my  nonbranded   toaster  pastry?    
  17. 17. Fire  is  made  of  gas  that  is  so  superhot  that  it  is  also  spiang  out  photons  that  we  can  see.    When   burnable  stuff  gets  hot  enough,  its  molecules  jiggle  so  fast  that  they  fly  apart  into  plain  old   atoms.    For  example,  wood  is  made  of  organic  molecules  that  include  carbon,  oxygen,  and   hydrogen.    Here’s  a  diagram  that  shows  where  the  atoms  are  and  how  they  are  bonded  together.   C   C   O   H   H   H   H  C   C   H   lots   more   stuff   lots  more  stuff   When  these  molecules  fly  apart,  the  carbon  atoms  interact  with  the   oxygen  molecules  in  the  air  to  form  carbon  dioxide.   C   O   O   C   C   O   H   H   H   H   C   O   O  
  18. 18. And  when  carbon  atoms  join  with  oxygen  molecules  to  make  carbon  dioxide,  it  creates  a   tremendous  extra  kick  of  jiggling  heat  energy.    So  the  superhot  carbon  dioxide  molecules  shoot   out  all  kinds  of  photons,  including  red,  yellow,  or  blue  ones  that  we  can  see.     They  also  float  upwards,  because  hot  gases  tend  to  float  on  top  of  cool  gases.    But  as  they  float,   they  cool  down.    Prey  soon  they  cool  down  enough  so  that  they  are  no  longer  shoo:ng  out   visible  photons,  just  the  invisible  infrared  ones  that  everything  shoots  out.     C   O   O   C   O   O   C   O   O   C   O   O   C   O   O  
  19. 19. It’s  not  really  jumping.    The  superhot  glowing  gas  is  so  hot  that  if  another  chunk  of   burnable  stuff  gets  too  close,  its  own  carbon  molecules  will  heat  up,  fly  apart,  and   start  making  their  own  superhot  glowing  gas.       So  how  can  fire  jump  from  one  burning  thing  to  another  if  it’s  just  gas?     Including  my  nonbranded  toaster  pastry.   Correct.       C   C   O   H   H   H   H  C   C   H   lots   more   stuff   lots  more  stuff   C   O   O   C   O   O   C   C   O   H   H   H   H   C   O   O   C   O   O  
  20. 20. Correct  in  every  respect.    Now  let  us  bombard   your  nonbranded  toaster  pastry  with  photons   un:l  it  jiggles  at  a  more  delicious  rate.   So,  to  recap:  fire  is  superhot  glowing  gas,  heat   is  jiggling,  and  my  nonbranded  toaster  pastry   and  I  are  constantly  shoo:ng  out  and   absorbing  invisible  photons.  
  1. A particular slide catching your eye?

    Clipping is a handy way to collect important slides you want to go back to later.

×