Electric Field vs Magnetic Field

Q.

The distance between the nearest node and antinode in a stationary wave is

[MP PET 1984; CBSE PMT 1993; AFMC 1996; RPET 2002]

1. l

2. 

3. 

4. 

Q.

If $\overrightarrow{E}$ and $\overrightarrow{B}$ are the electric and magnetic field vectors of E.M. waves then the direction of propagation of E.M. wave is along the direction of

1. $\overrightarrow{E}$

2. $\overrightarrow{B}$

3. $\overrightarrow{E}\times \overrightarrow{B}$

4. None of these

Q. Suppose that the electromagnetic wave in vacuum is
$\overrightarrow{E}=\{\left(3.1\frac{N}{C}\right)\cos \left[(1.8\frac{rad}{m}\right)y+(5.4\times {10}^6\frac{rad}{s})t]\hat{i}$
What is the frequency?

1. $8.6\times {10}^{5}Hz$
2. $4.3\times {10}^{5}Hz$
3. $8.6\times {10}^{3}Hz$
4. $4.3\times {10}^{3}Hz$

Q. An electromagnetic wave going through vacuum is described by $E=E_0\sin (kx-\omega t)$. Which of the following is/are independent of the wavelength?

1. $\omega$
2. $k\omega$
3. $\frac{k}{\omega }$
4. $k$

Q.

The magnetic field in a travelling electromagnetic wave has a peak value of 20 nT. The peak value of electric field strength is

1. 6 V/m

2. 9 V/m

3. 12 V/m

4. 3 V/m

Q. Find the amplitude of the electric field in a parallel beam of light of intensity $2.0W{m}^{-2}$

1. $28.5N{C}^{-1}$
2. $38.8N{C}^{-1}$
3. $43.2N{C}^{-1}$
4. $31.9N{C}^{-1}$

Q. The short-wavelength limit shifts by $26\text{pm}$ when the operating voltage in an X-ray tube is increased to $1.5$ times the original value. What was the original value of the operating voltage?

1. $15.93\text{kV}$
2. $36.78\text{kV}$
3. $8.12\text{kV}$
4. $25.56\text{kV}$