Conservation Of Mass and Energy -

 

 

 
Matter can’t be created or destroyed but can be
 converted into energy
 according to the formula ...

 

Nuclear Fireball

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Mass (kg) to Energy (J)


Equation

 

E

=

m

 c2

Units (J)

  

(Kg)

m/s

 

 

c - speed of light = 3.00 x 108 m/s

 

 

 

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Ex) How much energy would you get if you converted 2.0 Kg to energy?

 

 

E

=

m

 c2

Units (J)

  

(Kg)

 m/s

 

 

E = 2.0 Kg(3.00 x 108 m/s)2

 

 E = 1.8 x 1017 Joules

 

 

 

 

 

 

Finding the energy that can be obtained from the conversion of 1 proton (1 universal mass unit)

 

 

mass of a proton = 1.67 x 10-27 Kg

(p. 1 reference)

 

 

 

Plug into equation

E = mc2

 

 

 

E = (1.67 X 10-27 Kg)(3 x 108 m/s)2

       

 

= 1.5 x 10-10 Joules

 

 

 

 

Convert to eV:

 

        1 eV = 1.6 x 10 -19 Joules

 

 

 

 

E = 1.5 x 10-10 J
1.6 x 10 -19 J/eV

 

 

 = 9.31 x 102 Mev

 

 

or 931 MeV **

 

 

 

 

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To convert universal mass units to energy in MeV

1 proton
(universal mass unit)

converts

to 9.31 x 102 Mev
or 931 MeV

(p. 1 Reference)

 

 

(Mass/Energy Relationship)

 

 

 

 

Typical Regents Question ...

 

Ex) How much energy can be generated when 2 universal mass units are completely converted into energy?

 

1 universal mass unit = 931 MeV

 

Answer: 1862 MeV
(each universal mass unit
 converted produces 931 MeV)

 

 

 

 

Forces inside nucleus

 

1) Strong nuclear force
(A.K.A. 'strong force')

 

• holds nucleus together - very strong, short range

 

• operates at distance < 10-13 m

 

 

 

 

http://www.cassiopeiaproject.com/

| Onsite |

 

 

 

A) Binding Energy - amount of energy needed to separate nucleons (protons and neutrons) in nucleus.

 

 

Protons and neutrons in nucleus in large nuclei have slightly less mass than n and p in small nuclei

 

 

 


Mass of Assembled
Nucleus

<

Combined mass of an
 equivalent # of nucleons.

 

 

 


Lost mass
called mass defect

 

 

 

 

Mass Defect
  =
Binding energy

(mass lost is
converted to energy)

 

 

 

 

Ex) If the mass defect is .1 universal mass units then the binding energy = ....

 

(p. 1 Reference)

 

1 Universal mass unit

converts to

 

9.31 x 102 Mev

(p. 1 ref)

 

 

9.31 x 101 Mev

This movie is part of the collection: Prelinger Archives

Producer: Sutherland (John) Productions
Sponsor: General Electric Company
Audio/Visual: Sd, C
Keywords: Atomic-nuclear: Energy; Physics; Animation

Creative Commons license: Public Domain

 

 

 

 

 

 

 

 

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