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

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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:

[tex]-\frac{\partial B}{\partial x} = \mu_{0}\epsilon_{0}\frac{\partial E}{\partial t}[/tex]

and

[tex]\frac{\partial E}{\partial x} = -\frac{\partial B}{\partial t}[/tex]


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

[tex]-\frac{\partial B}{\partial x} = \mu_{0}\epsilon_{0}\frac{\partial E}{\partial t}[/tex]

and

[tex]\frac{\partial E}{\partial x} = -\frac{\partial B}{\partial t}[/tex]


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 [tex]\mu_o \epsilon_o[/tex] to k and [tex]\omega[/tex].
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 [tex]\mu_o \epsilon_o[/tex] to k and [tex]\omega[/tex].
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 [tex]B_m[/tex] on one side and a [tex]E_m[/tex] 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:

[tex]-\frac{\partial B}{\partial x} = \mu_{0}\epsilon_{0}\frac{\partial E}{\partial t}[/tex]

and

[tex]\frac{\partial E}{\partial x} = -\frac{\partial B}{\partial t}[/tex]


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

Thanks.

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