Concept explainers
(a)
The rest mass energy of the electron.
(a)
Answer to Problem 51PQ
The rest mass energy of an electron is
Explanation of Solution
Write the expression for the rest mass energy.
Here,
Conclusion:
Substitute
Convert
Here,
Therefore, the rest mass energy of an electron is
(b)
The total energy of an electron.
(b)
Answer to Problem 51PQ
The total energy of an electron is
Explanation of Solution
Write the expression for total energy of an electron.
Here,
Conclusion:
Substitute
Convert
Therefore, the total energy of an electron is
(c)
The speed of the electron.
(c)
Answer to Problem 51PQ
The speed of the electron is
Explanation of Solution
Write the expression of the relativistic kinetic energy of the particle.
Here,
Write the expression for Lorentz factor.
Substitute
Convert the unit of
Conclusion:
Substitute
Solve the equation further to find
Therefore, the speed of the electron is
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Chapter 39 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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