Thurs 27May:  

Key Concepts:  

           1/2  Day                 

Thurs - Fri 25-27 May (DEMO's)

Thurs 26 May 1/2 day

Fri 27 May: Auto Safety

Wed 1 Jun Review for final

Final: Thurs & Fri 2 & 3 June

Mon & Tues 6 & 7 June (Sub)

L#90: 1, 2, 8, 9, 12, 14, 15, 20  

(EM Radiation) Wed 8 May

Mouse Trap Car Thurs 9 June

L#91: 1, 2, 4, 5, 12 - 15, 20  

(EM Radiation) (due Fri 10 Jun)

L#93/95/96 (Relativity) (non-Sr's)

#93:1 - 3, 17, 18  #95: 1, 2, 6

#96: 1, 2, 5, 7

(due Mon 13 Jun)

#98 (Half-Life): 1 - 4, 6, 7, 10, 14, 16, 19,   (due Tues 14 June)

Wed Review Modern

Test: Thurs (90 - 98)

New Material:

• The Speed of Light is the same for all observers.

• However, Mass, Time and Length change.

• Mass, Time and Length will remain normal to the observer in their own reference frame. "Everything is relative"  (except light).

Relativity Factor:

• "c" is the speed of light "v" is the speed of the object in question

   

   

  For example, in space when an rocket reaches a speed of 0.999c,  its length was 1 meters, its mass was 1 kg and it traveled for 1 year (its time), what would we measure its

  a. length

  b. mass

  c. time

g = 1/ √1- (V²/c²)

 = 1 / √1- (0.999c²/c²)

= 1 / √1- (0.998) 

g= 1/√.002   -->  22.4 times

So,

Length is shorter

             1/22.4 or .045 meters

Mass is greater by 22.4 times =

                      22.4 meters

Time is greater by 22.4 times =

                      22.4 years

__

Half‑life:

The time it takes for ½ of the atoms to decay. If you have 200 atoms, how long will it take before you have 6 atoms left if the half-life is 15 days?

Start with  200 atoms

1^st ½ life: 100 atoms à 15 days

2^nd ½ life: 50 atoms à 30 days

3^rd ½ life: 25 atoms à 45 days

4^th ½ life: 12.5 atoms à 60 days

5^th ½ life: 6 atoms à 75 days

__________

____

Final: Tues 8 June