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if E=E(0)sin(kz-omegat) and B=B(0)(kz-om...

if `E=E_(0)sin(kz-omegat)` and `B=B_(0)(kz-omegat)` are electric and magnetic field produced by an electromagnetic wave travelling in +z direction in a medium. Then if `eta=(E_(0))/(B_(0))`, then the value of `eta` is `[mu`=permeability of a medium `epsilon=`permittivity of medium]

A

`sqrt(in//H)`

B

`sqrt(mu//en)`

C

`sqrt(mu in)`

D

`(1)/(sqrt(muin))`

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To find the value of \( \eta = \frac{E_0}{B_0} \) for the given electromagnetic wave equations, we can use the relationship between electric field \( E \), magnetic field \( B \), permeability \( \mu \), and permittivity \( \epsilon \) of the medium. ### Step-by-Step Solution: 1. **Understand the given equations**: - The electric field is given by \( E = E_0 \sin(kz - \omega t) \). - The magnetic field is given by \( B = B_0 \sin(kz - \omega t) \). - Here, \( E_0 \) and \( B_0 \) are the amplitudes of the electric and magnetic fields, respectively. 2. **Use the relationship between electric and magnetic fields**: - In an electromagnetic wave, the ratio of the electric field to the magnetic field in a medium is given by: \[ \eta = \frac{E_0}{B_0} \] 3. **Use the energy density concept**: - The energy density \( u_E \) of the electric field is given by: \[ u_E = \frac{1}{2} \epsilon E^2 \] - The energy density \( u_B \) of the magnetic field is given by: \[ u_B = \frac{1}{2} \frac{B^2}{\mu} \] 4. **Equate the energy densities**: - For electromagnetic waves, the energy densities of the electric and magnetic fields are equal: \[ u_E = u_B \] - Thus, we can write: \[ \frac{1}{2} \epsilon E_0^2 = \frac{1}{2} \frac{B_0^2}{\mu} \] - The \( \frac{1}{2} \) cancels out from both sides: \[ \epsilon E_0^2 = \frac{B_0^2}{\mu} \] 5. **Rearranging the equation**: - Rearranging gives: \[ \frac{E_0^2}{B_0^2} = \frac{1}{\mu \epsilon} \] 6. **Taking the square root**: - Taking the square root of both sides results in: \[ \frac{E_0}{B_0} = \frac{1}{\sqrt{\mu \epsilon}} \] 7. **Final expression for \( \eta \)**: - Therefore, we find: \[ \eta = \frac{E_0}{B_0} = \frac{1}{\sqrt{\mu \epsilon}} \] ### Conclusion: The value of \( \eta \) is given by: \[ \eta = \frac{1}{\sqrt{\mu \epsilon}} \]

To find the value of \( \eta = \frac{E_0}{B_0} \) for the given electromagnetic wave equations, we can use the relationship between electric field \( E \), magnetic field \( B \), permeability \( \mu \), and permittivity \( \epsilon \) of the medium. ### Step-by-Step Solution: 1. **Understand the given equations**: - The electric field is given by \( E = E_0 \sin(kz - \omega t) \). - The magnetic field is given by \( B = B_0 \sin(kz - \omega t) \). - Here, \( E_0 \) and \( B_0 \) are the amplitudes of the electric and magnetic fields, respectively. ...
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