In an electromagnetic wave, energy density associated with a magnetic field will be:
1.
2.
3.
4.
Which of the following statements is false regarding the properties of electromagnetic waves?
1. | Both electric and magnetic field vectors attain the maxima and minima at the same place and the same time |
2. | The energy in an electromagnetic wave is divided equally between electric and magnetic vectors |
3. | Both electric and magnetic field vectors are parallel to each other and perpendicular to the direction of propagation of the wave |
4. | These waves do not require any material medium for propagation |
The most penetrating radiation out of the following is:
1. x-rays
2. β-rays
3. -rays
4. γ-rays
The maxwell's equation:
is a statement of :
1. | Faraday's law of induction |
2. | Modified Ampere's law |
3. | Gauss's law of electricity |
4. | Gauss's law of magnetism |
If an electromagnetic wave of frequency f = 3 MHz passes from vacuum into a dielectric medium with relative permittivity K= 4.0, then:
1. | wavelength is 2 times and frequency becomes half |
2. | wavelength is half and frequency remains unchanged |
3. | wavelength and frequency both remain unchanged |
4. | None of the above |
A larger parallel plate capacitor, whose plates have an area of 1 , separated from each other by 1 mm, is being charged at a rate of 25.8 V/s. If the plates have dielectric constant 10, then the displacement current at this instant is:
1. 25
2. 11
3. 2.2
4. 1.1
A plane electromagnetic wave travels in free space along x-axis. At a particular point in space, the electric field along y-axis is 9.3 . The magnetic induction is:
1.
2.
3.
4.
Light is a kind of wave. The wavelength of visible light ranges from about 4000 \(\overset{o}{A}\) to 7000 \(\overset{o}{A}\). Which of the following statements is false?
1. | \(\overset{o}{A}\) | Ultraviolet light has a wavelength shorter than 4000
2. | Infrared light has a wavelength longer than 7000 \(\overset{o}{A}\) |
3. | Red light has a wavelength near about 7000 \(\overset{o}{A}\) |
4. | Violet light has a wavelength near about 7000 \(\overset{o}{A}\) |
If a source is transmitting an electromagnetic wave of frequency , then the wavelength of the electromagnetic wave transmitted from the source will be:
1. | 36.6 m | 2. | 40.5 m |
3. | 42.3 m | 4. | 50.9 m |
I: | Light can travel in vacuum but sound cannot do so. |
II: | Light is an electromagnetic wave and sound is a mechanical wave. |
1. | Both I and II are true and II is the correct explanation of I. |
2. | Both I and II are true but II is not the correct explanation of I. |
3. | I is true but II is false. |
4. | I is false but II is true. |