Relating B and E in an electromagnetic wave

In summary, the electric and magnetic fields in an electromagnetic wave are perpendicular to each other and oscillate in a synchronized manner, following the electromagnetic wave equation B = E/c. The amplitudes of these fields are directly proportional to each other, and the speed of light is determined by the properties of the medium in which it is traveling. The frequency and wavelength of an electromagnetic wave have an inverse relationship, and the fields cannot exist without each other as they are generated by each other.
  • #1
Revvi
8
0

Homework Statement



I need to determine B(rms) in terms of E(max) given a standard E-M wave.

Homework Equations



E = cB

The Attempt at a Solution



I assumed that B(max) is sqrt(2) x B(rms) and then just plugged in for B(max) in the equation above. Am I right in assuming the rms value involves a square root? (I get confused if it's 2 or sqrt(2))
 
Physics news on Phys.org
  • #2
You are right. The max value is greater than the rms value by a factor of sqrt(2).
 

1. What is the relationship between the electric and magnetic fields in an electromagnetic wave?

The electric and magnetic fields in an electromagnetic wave are perpendicular to each other and oscillate in a synchronized manner. This means that when the electric field is at its maximum strength, the magnetic field is at its minimum strength, and vice versa. This relationship is known as the electromagnetic wave equation: B = E/c, where B is the magnitude of the magnetic field, E is the magnitude of the electric field, and c is the speed of light.

2. How do the amplitudes of the electric and magnetic fields relate in an electromagnetic wave?

The amplitudes of the electric and magnetic fields in an electromagnetic wave are directly proportional to each other. This means that when the amplitude of the electric field increases, the amplitude of the magnetic field also increases by the same factor. This is because the two fields are generated by the same source - the changing electric field.

3. Why do electromagnetic waves propagate at the speed of light?

Electromagnetic waves propagate at the speed of light because they are composed of oscillating electric and magnetic fields, which are both properties of light. The speed of light is determined by the properties of the medium in which it is traveling, and in a vacuum, it is equal to approximately 3 x 10^8 meters per second.

4. How does the frequency of an electromagnetic wave relate to its wavelength?

The frequency of an electromagnetic wave and its wavelength have an inverse relationship. This means that as the frequency of the wave increases, its wavelength decreases. This can be mathematically represented by the equation c = fλ, where c is the speed of light, f is the frequency, and λ is the wavelength.

5. Can the electric and magnetic fields in an electromagnetic wave exist without each other?

No, the electric and magnetic fields in an electromagnetic wave are inseparable. This is because they are generated by each other, meaning that the changing electric field creates the magnetic field, and the changing magnetic field creates the electric field. Without one, the other cannot exist.

Similar threads

  • Introductory Physics Homework Help
Replies
21
Views
3K
  • Introductory Physics Homework Help
Replies
3
Views
2K
  • Introductory Physics Homework Help
Replies
5
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
902
  • Introductory Physics Homework Help
Replies
10
Views
926
  • Introductory Physics Homework Help
Replies
6
Views
744
  • Introductory Physics Homework Help
Replies
4
Views
6K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
1K
Back
Top