Solving for a neutralizing B0 in a Thomson Cathode Ray (Algebra?)

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SUMMARY

The discussion centers on resolving issues related to calculating a neutralizing B0 in a Thomson Cathode Ray setup. Participants clarified that the units for Tesla are equivalent, specifically T = kg/(s·C) = N·s/(m·C), which the original poster misunderstood. The poster encountered difficulties with their calculations despite confirming values for constants like the charge and mass of the electron. Ultimately, the resolution involved recognizing the necessity of raising values to the 1/2 power, highlighting the importance of unit consistency in physics problems.

PREREQUISITES
  • Understanding of electromagnetic units, particularly Tesla
  • Familiarity with Thomson Cathode Ray experiments
  • Basic algebra skills for manipulating equations
  • Knowledge of fundamental constants, such as the charge and mass of the electron
NEXT STEPS
  • Study the principles of electromagnetic fields in the context of Thomson Cathode Rays
  • Learn about unit conversions and dimensional analysis in physics
  • Explore the significance of constants in physics calculations
  • Review algebraic techniques for solving equations involving powers and roots
USEFUL FOR

Physics students, educators, and anyone involved in experimental physics or electromagnetic theory will benefit from this discussion, particularly those working with Thomson Cathode Ray setups.

garthenar
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Homework Statement
In your experiment, you measure a total deflection of 4.12 cm when an electric field of 1.10×103V/m is established between the plates (with no magnetic field present). When you add the magnetic field as described in Part C, to what value do you have to adjust its magnitude B0 to observe no deflection?

Assume that the plates are 6.00 cm long and that the distance between them and the screen is 12.0 cm.
Express your answer numerically in tesla.
Relevant Equations
deltaY = eE0d(d+2L)/2m(v0)^2

V0 = E0/B0
I've attached a picture from the problem, the given equations, and my work so far.

I knew I had a problem when My units wouldn't check out. This should just be simple algebra but It's not working. Please help me to understand what I am doing wrong.
 

Attachments

  • Fig1 from Thomeson Experement.PNG
    Fig1 from Thomeson Experement.PNG
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  • thomson exp ptD.pdf
    thomson exp ptD.pdf
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I haven't gone through your whole attempted solution yet, but regarding your units,

\mathrm{T = \frac{kg}{s \cdot C} = \frac{N \cdot s}{m \cdot C}}

These are all the same units, equivalent to 1 Tesla. You've indicated near the end of your work that they are not the same, but they in fact are the same. If it helps, recall that

\mathrm{N = \frac{kg \cdot m}{s^2}}
 
This is unfortunate. I confirmed what you told me about the units but my answer is still wrong.

I have double checked the values they gave me, adjusted the resolution of my constants (eg. the charge and mass of the electron) and even tried changing signs. My answer makes sense to me but is apparently wrong. And the units agree with the setup being right so I believe it has to be my values

... I forgot to raise everything to the 1/2 power... Well at least I learned something valuable about the units of magnetic field. I'll make sure to add that to my note cards. (Units are life)

Thank you for your help and have a good night.
 
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