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Bestimmung der Masse von Elektronen

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Level 6 -

Exercise

https://texercises.com/exercise/bestimmung-der-masse-von-elektronen/

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The following quantities appear in the problem: Masse \(m\) / elektrische Ladung \(q, Q\) / Magnetische Flussdichte \(B\) / Kraft \(F\) / elektrische Spannung \(U\) / Energie \(E\) / Geschwindigkeit \(v\) / Radius \(r\) /

The following formulas must be used to solve the exercise: \(E = qU \quad \) \(E_{\rm \scriptscriptstyle kin} = \dfrac12 mv^2 \quad \) \(F = qvB \quad \) \(F = m\dfrac{v^2}{r} \quad \)

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Exercise:
Mit einem Kathodenstrahlrohr kann die Masse von Elektronen bestimmt werden. Welche Masse errechnet man für ein Elektron falls es mit UO beschleunigt worden ist dann rechtwinklig zu den Feldlinien in ein magnetisches Feld mit BO Flussdichte fliegt und dort einen Kreis mit rO Radius beschreibt? Die Ladung der Elektronen kann als aus dem Millikan-Versuch bekannt vorausgesetzt werden; sie beträgt nce.

Solution:
Kombiniert man die Gleichung für die erreichte Geschwindigkeit aufgrund einer Beschleunigungsspannung Ekin Epot fracmv^ qU v^ fracqUm sowie die Gleichung für ein aufgrund der Lorentzkraft kreises Teilchen sscFL &mustbe sscFZ qvB fracmv^r v fracqrBm v^ fracq^r^B^m^ so erhält man: fracqUm fracq^r^B^m^ m fracqr^B^U fracnce qtyr^ qtyB^ U m

Meta Information

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Contained in these collections:

Beschleunigungsspannung und Kreisbahn by TeXercises

1 | 6
Lorentzkraft auf Teilchen 2 by uz

7 | 10
Anwendungen Lorentzkraft by aej

2 | 4

Asked Quantity: Masse \(m\) in Kilogramm \(\rm kg\)

Attributes & Decorations

Tags	brownsche bewegung, elektromagnetismus, kathodenstrahlröhre, lorentzkraft, magnetfeld, physik, röhre, teilchen
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Difficulty	(4, default)
Points	4 (default)
Language	(Deutsch)
Type	Calculative / Quantity
Creator	uz
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