How Do You Derive Electron Energy in Physics Equations?

AI Thread Summary
The discussion focuses on deriving electron energy in physics equations, with participants seeking clarification on specific algebraic steps and the meaning of variables. One user is struggling to transition from one equation to another and requests guidance on the algebra involved. Questions arise regarding the definition of Ee, which is identified as the total energy of the electron, and the origin of the value 5.49x10-4, clarified as the electron mass in atomic mass units. Participants provide hints on solving algebraic expressions and emphasize the importance of units in calculations. Understanding these concepts is crucial for successfully deriving the equation for electron energy.
Woopa
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Homework Statement
Derive the equation
Relevant Equations
E=P^2/2m
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I am having trouble understanding this derivation and need some guidance.

1) I tried solving the algebra from the first equation to the second equation circled in red. Can someone please help with what algebra steps, I cannot solve to the circled solution.

2) What does Ee stand for? Is it Total energy of the electron?

3) Where did the value 5.49x10-4 come from? This does not appear to be the mass of the electron.
 
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1) Please show us your attempt.

2) Kinetic energy of the electron

3) it is the electron mass’ numerical value in the atomic mass unit u (which also the proton mass is given in). Units are important.
 
Woopa said:
Homework Statement:: Derive the equation
Relevant Equations:: E=P^2/2m

1) I tried solving the algebra from the first equation to the second equation circled in red. Can someone please help with what algebra steps, I cannot solve to the circled solution.
What did you try? Hint: $$\frac{A}{B} + \frac{A}{C} = A(\frac{1}{B} + \frac{1}{C})$$

Hint: Find a common denominator to express that sum of fractions as a single fraction.
 
... or, just multiply by ##BC##.
 
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