Electromotive force and trigonometry

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SUMMARY

The discussion centers on the application of Faraday's law of electromagnetic induction, specifically the formula for electromotive force (EMF) represented as \(\epsilon = -N \frac{\Delta{\phi}}{\Delta{t}} = -N \frac{\Delta{(BA\cos{\theta})}}{\Delta{t}}\). Participants debated whether the correct expression for EMF should involve a sine function instead of a cosine function when applying calculus, ultimately concluding that the choice between sine and cosine is arbitrary due to the constant phase shift in the angle. The consensus is that the EMF can be expressed as \(\epsilon = NBA\omega\cos{(\omega t)}\) without loss of generality.

PREREQUISITES
  • Understanding of Faraday's law of electromagnetic induction
  • Basic knowledge of calculus and differentiation
  • Familiarity with trigonometric functions, specifically sine and cosine
  • Concept of angular frequency (\(\omega\)) in oscillatory motion
NEXT STEPS
  • Study the derivation of Faraday's law in detail
  • Explore applications of calculus in physics, particularly in electromagnetism
  • Investigate the implications of phase shifts in trigonometric functions
  • Learn about angular frequency and its role in oscillatory systems
USEFUL FOR

Students of physics, educators teaching electromagnetism, and anyone interested in the mathematical foundations of electromagnetic induction.

mcastillo356
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TL;DR
Contradictory result
Faraday's law:
\epsilon=-N\dfrac{\Delta{\phi}}{\Delta{t}}=-N\dfrac{\Delta{(BA\cos{\theta})}}{\Delta{t}}=-N\dfrac{\Delta{(BA\cos{(\omega t)})}}{\Delta{t}}
Applying calculus
\epsilon=NBA\omega\cos{(\omega t)}
Shouldn't it be \epsilon=NBA\omega\sin{(\omega t)}, just if I apply limits?
Thanks
 
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Assuming A,B don't depend on t, I think you are right!
 
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There is only one way: if t_0=NBA\omega. But this is not calculus. Or yes?
 
The point of t=0 is generally arbitrary, it doesn't matter if your angle follows a sine, a cosine, or anything else with a constant phase shift.
 
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Thanks, mfb!
 
Thank's, Math_QED
 

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