MCQ Questions for Class 12 Physics Chapter 8 Electromagnetic Waves Part-1 with Answers

Electromagnetic Waves Part-1 Class 12 Physics MCQs Questions with Answers

Check the below NCERT MCQ Questions for Class 12 Physics Chapter 8 Electromagnetic Waves Part-1 with Answers Pdf free download. MCQ Questions for Class 12 Physics with Answers were prepared based on the latest exam pattern. We have Provided Electromagnetic Waves Part-1 Class 12 Physics MCQs Questions with Answers to help students understand the concept very well.

Class 12 Physics Chapter 8 Quiz

Class 12 Physics Chapter 8 MCQ Online Test

You can refer to NCERT Solutions for Class 12 Physics Chapter 8 Electromagnetic Waves Part-1 to revise the concepts in the syllabus effectively and improve your chances of securing high marks in your board exams.

Electromagnetic Waves Part-1 Class 12 Physics MCQ online test

Q1.	The dimensional formula of \(\vec{E}\) is:
	A.[MLT^-2A^-1]
	B.[MLT^-3A^-1]
	C.[MLT^-2A^-2]
	D.None of these

Ans: [MLT^-3A^-1]

Q2.	The dimensional formula of is:
	A.[MLT^-2A^-1]
	B.[ML⁰T^-2A^-1]
	C.[ML⁰T^-3A^-1]
	D.None of these

Ans: [ML⁰T^-2A^-1]

Q3.	Which of the following has the dimensions of current?
	A.ε₀ \(\vec{E}\).\(\vec{dt}\)
	B.µ₀ \(\vec{E}\).\(\vec{dt}\)
	C.\(\frac{\vec{B}.\vec{dl}}{µ_0}\)
	D.\(\frac{\vec{B}.\vec{dl}}{ε_0}\)

Ans: \(\frac{\vec{B}.\vec{dl}}{µ_0}\)

Q4.	Which of the following has the dimensions of charge?
	A.\(\frac{ε_0\vec{E}}{\vec{ds}}\)
	B.µ₀ \(\vec{E}\).\(\vec{ds}\)
	C.\(\frac{ε_0}{µ_0}\) \(\vec{E}\).\(\vec{ds}\)
	D.\(\frac{µ_0}{ε_0}\) \(\vec{E}\).\(\vec{ds}\)

Ans: \(\frac{ε_0\vec{E}}{\vec{ds}}\)

Q5.	Maxwell’s equation involving \(\frac{d}{dt}\) \(\vec{B}\) is obtained-from:
	A.Ampere’s law
	B.Gauss’s law
	C.Faraday’s law
	D.Biot-Savart’s law

Ans: Faraday’s law

Q6.	The dimensions of \(\vec{E}\), \(\vec{dl}\) are identical to that of:
	A.potential
	B.charge
	C.current
	D.None of these

Ans: potential

Q7.	Which of the following laws was modified by Maxwell by introducing the displacement current?
	A.Gauss’s law
	B.Ampere’s law
	C.Biot-Savart’s law
	D.None of these

Ans: Ampere’s law

Q8.	Choose the wave relevant to telecommunication :
	A.ultraviolet
	B.infrared
	C.microwave
	D.visible light

Ans: microwave

Q9.	Electromagnetic waves have a speed of
	A.3 × 10⁵ kms^-1
	B.3 × 10⁶ kms^-1
	C.3 × 10⁷ kms^-1
	D.3 × 10⁸ kms^-1

Ans: 3 × 10⁵ kms^-1

Q10.	Which of the following EMW has highest wavelength?
	A.X-ray
	B.ultraviolet rays
	C.infrared rays
	D.microwaves

Ans: infrared rays

Q11.	Displacement current is due to:
	A.the flow of electrons
	B.the Varying electric field
	C.the ionization of atmosphere
	D.the flow of protons

Ans: the Varying electric field

Q12.	Displacement current is always :
	A.equal to conduction current
	B.less than conduction current
	C.greater than conduction current
	D.the sum of current due to flow of positive and negative ions

Ans: equal to conduction current

Q13.	EMW are produced by:
	A.charge in uniform motion only
	B.charge at rest only
	C.accelerated or decelerated charge only
	D.all of the above

Ans: accelerated or decelerated charge only

Q14.	Who first demonstrated the existence of em waves?
	A.Hertz
	B.Maxwell
	C.Ampere
	D.Faraday

Ans: Hertz

Q15.	If \(\vec{B}\) is the magnetic field vector and \(\vec{E}\) is the electric field vector in an em wave, then which of the following relations is correct? Here c is the speed of fight:
	A.c = \(\frac{E}{B}\)
	B.c = BE
	C.c = \(\frac{B}{E}\)
	D.c = \(\frac{1}{EB}\)

Ans: c = \(\frac{E}{B}\)

Q16.	The dimensions of E/Bare same as that of:
	A.charge
	B.current
	C.velocity
	D.acceleration

Ans: velocity

Q17.	Name the law which states that a varying electric field produces a magnetic field:
	A.Biot-Savart’s law
	B.Faraday’s law
	C.Modified Ampere’s law
	D.None of these

Ans: Modified Ampere’s law

Q18.	The existence of EMW was experimentally established by :
	A.Sir S. C. Bose
	B.Maxwell
	C.Marconi
	D.Hertz

Ans: Sir S. C. Bose

Q19.	An EMW of v = 3 MHz passes from vacuum into dielectric medium with permittivity E_r = 4, then:
	A.Wavelength is doubled and the frequency remains unchanged
	B.Wavelength is doubled and the frequency become half
	C.Wavelength is halved and the frequency remains unchanged
	D.Wavelength and frequency both remain unchanged