# NCERT Class 12/MCQ Questions for Class 12 Physics Chapter 8 Electromagnetic Waves Sample Test,Sample questions

## Question: `Ampereâ€™s circuital law was modified by:`

1.Laplace

2.Gauss

3.Maxwell

4.Hertz

Posted Date:-2021-12-17 08:14:40

## Question: `An EMW of v = 3 MHz passes from vacuum into dielectric medium with permittivity Er = 4, then:`

1.Wavelength is doubled and the frequency remains unchanged

2.Wavelength is doubled and the frequency become half

3.Wavelength is halved and the frequency remains unchanged

4.Wavelength and frequency both remain unchanged

Posted Date:-2021-12-17 08:11:23

## Question: `Choose the wave relevant to telecommunication :`

1.ultraviolet

2.infrared

3.microwave

4.visible light

Posted Date:-2021-12-17 07:58:17

## Question: `Choose the wrong statement?`

1.Electromagnetic waves are transverse

2.Electromagnetic waves travel with the speed of light in free space

3.Electromagnetic waves are produced by accelerating charges

4.Electromagnetic waves travel with the same speed in all media

Posted Date:-2021-12-17 08:12:58

## Question: `Displacement current is always :`

1.equal to conduction current

2. less than conduction current

3.greater than conduction current

4. the sum of current due to flow of positive and negative ions

Posted Date:-2021-12-17 08:02:35

## Question: `Displacement current is due to:`

1.the flow of electrons

2.the Varying electric field

3.the ionization of atmosphere

4.the flow of protons

Posted Date:-2021-12-17 08:00:53

## Question: `Electromagnetic waves have a speed of`

1.(a) 3 Ã— 105 kms-1

2.3 Ã— 106 kms-1

3.3 Ã— 107 kms-1

4.3 Ã— 108 kms-1

Posted Date:-2021-12-17 07:59:09

## Question: `EMW are produced by:`

1.charge in uniform motion only

2.charge at rest only

3.accelerated or decelerated charge only

4.All the above

Posted Date:-2021-12-17 08:03:56

## Question: `Frequency of a wave is 6 Ã— 1015. Hz. The wave is :`

2.Microwave

3.X-ray

4.Ultra violet

Posted Date:-2021-12-17 08:12:11

## Question: ```Light Year is the unit of: ```

1.distance

2.time

3.energy

4.intensity of light

Posted Date:-2021-12-17 08:15:24

## Question: ```Name the law which states that a varying electric field produces a magnetic field: ```

1.Biot-Savartâ€™s law

3.Modified Ampereâ€™s law

4.None of the above

Posted Date:-2021-12-17 08:06:43

## Question: `Solar radiation is :`

1.transverse EMW

2. longitudinal EMW

3.Both of the above

4.None of the above

Posted Date:-2021-12-17 08:13:51

## Question: `The dimensional formula of Eâƒ— is:`

1.[MLT-2A-1]

2. [MLT-3A-1]

3.[MLT-2A-2]

4.None of the above

Posted Date:-2021-12-16 18:23:15

## Question: `The dimensional formula of is`

1. [MLT-2A-1]

2.[ML0T-2A-1]

3.[ML0T-3A-1]

4.None of the above

Posted Date:-2021-12-17 07:54:28

## Question: `The dimensions of E/Bare same as that of:`

1.charge

2.current

3.velocity

4.acceleration

Posted Date:-2021-12-17 08:05:46

## Question: `The existence of EMW was experimentally established by :`

1.Sir S. C. Bose

2.Maxwell

3.Marconi

4.Hertz

Posted Date:-2021-12-17 08:07:30

## Question: `Which of the following EMW has highest wavelength?`

1. X-ray

2.ultraviolet rays

3.infrared rays

4.microwaves

Posted Date:-2021-12-17 07:59:54

## Question: `Which of the following laws was modified by Maxwell by introducing the displacement current?`

1.Gaussâ€™s law

2.Ampereâ€™s law

3.Biot-Savartâ€™s law

4.None of the above

Posted Date:-2021-12-17 07:55:39

1.Hertz

2.Maxwell

3.Ampere