UH PHYS 1302 - Ch32 (15 pages)

Previewing pages 1, 2, 3, 4, 5 of 15 page document View the full content.
View Full Document

Ch32



Previewing pages 1, 2, 3, 4, 5 of actual document.

View the full content.
View Full Document
View Full Document

Ch32

243 views

ch 32 study guide


Pages:
15
School:
University of Houston
Course:
Phys 1302 - Introductory to Physics II

Unformatted text preview:

Chapter 32 Nuclear Physics and Nuclear Radiation 1 The Constituents and Structure of Nuclei The nucleus of an atom consists of positively charged protons and neutral neutrons Protons and neutrons are called nucleons We characterize nuclei by the number of protons and neutrons they contain atomic number Z the number of protons in a nucleus neutron number N the number of neutrons in a nucleus mass number A Z N the total number of nucleons The notation we used to represent the composition of the nucleus is A Z X where X represents the symbol for a particular element For example the symbol for hydrogen is H the symbol for carbon is C the symbol for sodium is N a Since you are given A and Z in this notation you can find N A Z All nuclei of a given element have the same number of protons same atomic number However they may have different numbers of neutrons Nuclei of the same element same atomic number Z that have different numbers of neutrons are called 13 isotopes For example 12 6 C and 6 C are isotopes of carbon There is a unit of mass called the atomic mass unit u defined such that one atom of 12 6 C is exactly 12 u 1u 1 660540 10 27 kg A proton has a mass of 1 007276 u and a neutron has a mass of 1 008665 u The average radius of a nucleus of mass number A is r 1 2 10 15 m A1 3 L Whitehead 1 1 Phys 1302 1 fermi 1 femtometer fm 10 15 m Named after Enrico Fermi Using the radius of a nucleus we can find an expression for the density of a nucleus We ll use the approximation that the proton and neutron have the same mass 1u 1 67 10 27 kg M V A 1 67 10 27 kg 4 r3 3 A 1 67 10 27 kg 4 1 2 10 15 mA1 3 3 3 A 1 67 10 27 kg 4 1 2 10 15 m 3 A 3 1 67 10 27 kg 4 1 2 10 15 m 3 3 2 3 1017 kg m3 2 The density is independent of the mass number all nuclei have approximately the same density Protons in the nucleus exert repulsive electric forces on each other What keeps the nucleus from flying apart There must be another stronger force that overcomes the electric force The force that



View Full Document

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...
Login

Join to view Ch32 and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Ch32 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?