Proving EM Waves Equations: E = Emsin(kx-ωt) and B = Bmsin(kx-ωt)

AI Thread Summary
The discussion focuses on proving that the electric field E = Emsin(kx-ωt) and magnetic field B = Bmsin(kx-ωt) satisfy the equations -∂B/∂x = μ₀ε₀∂E/∂t and ∂E/∂x = -∂B/∂t. Participants suggest substituting the expressions for E and B into the differential equations, taking derivatives, and relating μ₀ε₀ to k and ω. There is a mention of potential complications with B_m and E_m appearing on different sides of the equations. The conversation also references starting with Maxwell's equations as a foundational approach. Overall, the thread emphasizes the methodical approach to solving the equations through substitution and differentiation.
noppawit
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Show that the electric field: E = Emsin(kx-ωt) and magnetic field: B=Bmsin(kx-ωt) satisfy the following equations:

-\frac{\partial B}{\partial x} = \mu_{0}\epsilon_{0}\frac{\partial E}{\partial t}

and

\frac{\partial E}{\partial x} = -\frac{\partial B}{\partial t}


I have no idea about this. Would you please guide me for solving this.

Thanks.
 
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Your equations didn't come out properly so we can't help you.
 
Sorry for my bad Latex typing. :redface:

I've edited.
 
noppawit said:
Show that the electric field: E = Emsin(kx-ωt) and magnetic field: B=Bmsin(kx-ωt) satisfy the following equations:

-\frac{\partial B}{\partial x} = \mu_{0}\epsilon_{0}\frac{\partial E}{\partial t}

and

\frac{\partial E}{\partial x} = -\frac{\partial B}{\partial t}


I have no idea about this. Would you please guide me for solving this.

Thanks.

In a situation like this, the usual procedure is to substitute the two given expressions into the differential equation, take the derivatives and see what happens. As I look at what you've been given (without working it out myself) I think you may have to figure out how to relate \mu_o \epsilon_o to k and \omega.
That should get you started. Let us know if you run into trouble.
 
AEM said:
In a situation like this, the usual procedure is to substitute the two given expressions into the differential equation, take the derivatives and see what happens. As I look at what you've been given (without working it out myself) I think you may have to figure out how to relate \mu_o \epsilon_o to k and \omega.
That should get you started. Let us know if you run into trouble.

Upon reading my previous post, I see a small problem with what I wrote. When you substitute the expressions for E an B into each equation, you'll end up with a B_m on one side and a E_m on the other. That's a nuisance. However, I'll bet you can figure out a way to combine those two equations into one equation and then do the substitution.
 
noppawit said:
Show that the electric field: E = Emsin(kx-ωt) and magnetic field: B=Bmsin(kx-ωt) satisfy the following equations:

-\frac{\partial B}{\partial x} = \mu_{0}\epsilon_{0}\frac{\partial E}{\partial t}

and

\frac{\partial E}{\partial x} = -\frac{\partial B}{\partial t}


I have no idea about this. Would you please guide me for solving this.

Thanks.

IIRC, you would start with Maxwell's equations...
 
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