Couple of Questions Regarding EM Waves

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SUMMARY

This discussion focuses on electromagnetic (EM) waves, specifically addressing the propagation direction, behavior of point charges in EM fields, antenna polarization, and the properties of standing waves. It is established that measuring the electric (E) and magnetic (B) fields at a point provides vector information about the wave's direction if the field is monochromatic. A point charge +q will oscillate in response to a sinusoidal EM wave, and vertical antennas indicate vertical E-field polarization. Furthermore, electromagnetic standing waves possess both energy and momentum, contingent on the non-zero cross product of the E and B fields.

PREREQUISITES
  • Understanding of electromagnetic wave properties
  • Familiarity with vector fields in physics
  • Knowledge of antenna design and polarization
  • Basic principles of electric charges and forces
NEXT STEPS
  • Study the relationship between E-field and B-field in EM wave propagation
  • Explore the effects of EM waves on charged particles
  • Research antenna polarization and its implications for signal reception
  • Investigate the energy and momentum of electromagnetic fields
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Physics students, electrical engineers, and professionals working with electromagnetic theory and applications in communication technologies.

virtuosowanaB
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I'm a little unsure of my own answers to these questions. Hopefully I'll clear up my misconceptions.

1. If I measure the E-field and B-field at a point in space where there is an EM wave, would I be able to determine the direction it propagates from?

My Ans: I don't think so, since when you do a reading a a point, you only get the scalar value

2. If a point charge +q lies on the x-axis and is in the path of a sinousoidal EM wave, will the point charge move?

My Ans: I believe it would just oscillate at that point

3. Most vehicles have got upright and vertical receiving antennas. What does this tell about the E-field polarization of the radio waves that are being broadcasted?

My Ans: It is vertical.

4. Does electromagnetic standing waves have energy? Does it have momentum?

My Ans: Yes. Yes


Could anyone go through my answers and let me know if I have any misconceptions?
Thanks!
 
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The field is a vector, if you measure it at any point it will still be a vector, if you measure the field at a point you will know about the field at that point, if you also know that the field is monochromatic you will know which direction it is headed towards.
Yes the point charge will experience a force.
Yes as long as the cross product between the E and B fields is non-zero there will be field momentum, all foelds on the other hand have energy.
 

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