1. | the energy density in electric field is equal to energy density in magnetic field. |
2. | they travel with a speed equal to \(\frac{1}{\sqrt{\mu_0~ \epsilon_0}} .\) |
3. | they originate from charges moving with uniform speed. |
4. | they are transverse in nature. |
An electromagnetic wave is moving along negative \(\text{z (-z)}\) direction and at any instant of time, at a point, its electric field vector is \(3\hat j~\text{V/m}\). The corresponding magnetic field at that point and instant will be: (Take \(c=3\times10^{8}~\text{ms}^{-1}\) )
1. | \(10\hat i~\text{nT}\) | 2. | \(-10\hat i~\text{nT}\) |
3. | \(\hat i~\text{nT}\) | 4. | \(-\hat i~\text{nT}\) |
1. | \(3 \times 10^{-8} \text{cos}\left(1.6 \times 10^3 x+48 \times 10^{10} t\right) \hat{i}~\text{ V/m}\) |
2. | \(3 \times 10^{-8} \text{sin} \left(1.6 \times 10^3 {x}+48 \times 10^{10} {t}\right) \hat{{i}}~ \text{V} / \text{m}\) |
3. | \(9 \text{sin} \left(1.6 \times 10^3 {x}-48 \times 10^{10} {t}\right) \hat{{k}} ~~\text{V} / \text{m}\) |
4. | \(9 \text{cos} \left(1.6 \times 10^3 {x}+48 \times 10^{10} {t}\right) \hat{{k}}~~\text{V} / \text{m}\) |
1. | \(1:1\) | 2. | \(1:c\) |
3. | \(1:c^2\) | 4. | \(c:1\) |