JEE Electromagnetic Waves PYQs
JEE Electromagnetic Waves PYQs matter as a component of JEE Physics syllabus. They assist you to know the types of the questions asked in this chapter and the extent to which you are familiar with the key concepts, which are electromagnetic waves, electric field, magnetic field, speed of light, displacement current, nature of waves, and the electromagnetic spectrum.
In the exam, questions from electromagnetic waves usually come as direct concept-based questions or simple numerical problems. The good thing is that this chapter is not as difficult as it may look in the beginning. Once your basics are clear and you understand the main ideas properly, solving questions becomes much easier. With regular revision and smart practice, this chapter can become one of the scoring parts of JEE Physics.
In this blog, you will find a simple formula PDF, a section for important JEE Electromagnetic Waves PYQs in download format, a few practice questions with answers, and some extra questions to solve on your own. You will also learn about common mistakes students often make and a few easy tips that can help you save time in the exam.
JEE Electromagnetic Waves Important PYQs PDF
This PDF can include the most important previous year questions from electromagnetic waves. It may cover topics like the nature of electromagnetic waves, electric and magnetic fields in EM waves, displacement current, speed of EM waves, energy transfer, and the electromagnetic spectrum.
Practicing these questions will help you understand the exam pattern better. It will also improve your speed, accuracy, and confidence before the exam.
Important Formulas for JEE Electromagnetic Waves PYQs
You only need a few important formulas and ideas to solve most electromagnetic waves questions in JEE. These formulas help you understand field relations, wave speed, energy flow, and wave behaviour more clearly.
You can download the full formula PDF from the link above. Here is a quick look at some of the main formulas:
Concept | Formula |
Speed of Electromagnetic Wave | c = 1 / √(μ₀ε₀) |
Relation Between Speed, Frequency, and Wavelength | c = νλ |
Electric and Magnetic Field Relation | E = cB |
Energy Density of Electric Field | uₑ = ½ ε₀E² |
Energy Density of Magnetic Field | uᵦ = B² / 2μ₀ |
Total Energy Density | u = ε₀E² = B² / μ₀ |
Ratio of Electric to Magnetic Field | E/B = c |
Momentum of EM Radiation | p = E/c |
Radiation Pressure | P = I/c |
Radiation Pressure on Perfect Reflector | P = 2I/c |
These formulas are commonly used in questions based on wave speed, field strength, energy density, radiation pressure, and the electromagnetic spectrum. If you revise them properly, many JEE questions start to feel much easier.
Top 5 Common Mistakes to Avoid in JEE Electromagnetic Waves PYQs
Many students feel this chapter is confusing at first because it includes both field concepts and wave concepts. But in most cases, mistakes happen because small details are missed while solving. Here are some common mistakes you should avoid:
Confusing the directions of electric field and magnetic field
In an electromagnetic wave, the electric field and magnetic field are perpendicular to each other. Both are also perpendicular to the direction in which the wave travels. Many students mix up these directions.
Forgetting the relation E = cB
This is one of the most important formulas in this chapter. Students often remember electric field and magnetic field separately, but forget the relation between them.
Mixing up frequency and wavelength in the electromagnetic spectrum
In the spectrum, frequency and wavelength change in opposite ways. When frequency increases, wavelength decreases. This creates confusion for many students.
Not remembering the order of the electromagnetic spectrum properly
The sequence of radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays should be clear. Students often mix up this order.
Not reading theory questions carefully
This chapter has many concept-based questions. A small misunderstanding of words like transverse, perpendicular, or propagation can lead to a wrong answer.
List of JEE Electromagnetic Waves PYQs
Here is a short set of JEE-style electromagnetic waves questions for practice. These include common question types from wave speed, field relations, spectrum, and radiation pressure. Solving them regularly can help you become faster and more confident.
Question 1
An electromagnetic wave of frequency 100 MHz propagates through a medium of conductivity, $$\sigma$$ = 10mho/m. The ratio of maximum conduction current density to maximum displacement current
density is ___________.
[Take $$\frac{1}{4\pi \epsilon_{0}} = 9 \times 10^{9} Nm^{2}/C^{2}$$]
correct answer:- 1800
Question 2
The electric field in a plan a electromagnetic wave is given by :
$$E_{y}=69\sin[0.6\times10^{3}x-1.8\times10^{11}t]V/m$$
The expression for magneticfield associated with this electromagnetic wave is ___ T.
correct answer:- 4
Question 3
A laser beam has intensity of $$4.0 \times 10^{14} W/m^{2}.$$ The amplitude of magnetic field associated with beam is____________T. (Take $$\epsilon_{0}= 8.85 \times 10^{-12} C^{2}/Nm^{2}$$ and $$c= 3 \times 10^{8} m/s$$ )
correct answer:- 2
Question 4
The equation of the electric field of an electromagnetic wave propagating through free space is given
by: E=$$\sqrt{377}$$ $$\sin(6.27\times10^{3}t-2.09\times 10^{-5}x)N/C$$
The average power of the electromagnetic wave is $$\left(\frac{1}{\alpha}\right)W/m^{2}$$. The value of $$\alpha$$ is______
$$\left(Take \sqrt{\frac{\mu_{\circ}}{\epsilon_{\circ}}}=377 in SI units \right)$$
correct answer:- 2
Question 5
The electric field of a plane electromagnetic wave, travelling in an unknown non-magnetic medium is given by,
$$ E_{y}=20 \sin (3\times 10^{6}x - 4.5\times 10^{14}t)V/m $$
(where $$x, t$$ and other values have S.I. units). The dielectric constant of the medium iS_________
(speed oflight in free space is $$ 3\times 10^{8} m/s $$)
correct answer:- 4
Question 6
Match the LIST-I with LIST-II

Choose the correct answer from the options given below:
correct answer:- 3
Question 7
The electric field of an electromagnetic wave travelling through a medimn is given by $$\overrightarrow{E}(x,t)=25\sin(2.0\times 10^{15}t-10^{7}x)\widehat{n}$$ then the refractive index of the medium is______.
(All given measurement are in SI uits)
correct answer:- 1
Question 8
The ratio of speeds of electromagnetic waves in vacuum and a medium, having dielectric constant $$k = 3$$ and permeability of $$ \mu = 2 \mu_{0}$$, is
($$\mu_{0}$$ = permeability of vacuum)
correct answer:- 2
Question 9
A plane electromagnetic wave is moving in free space with velocity $$c=3\times 10^{8} m/s$$ and its eleclric field is given as $$\overrightarrow{E}=54\sin (kz-\omega t)\widehat{j} V/m$$, where $$\widehat{j}$$ is the unit vector along y-axis. The magnetic field vector $$\overrightarrow{B}$$ of the wave is :
correct answer:- 3
Question 10
A parallel plate capacitor of area $$A=16 cm^{2}$$ and separation between the plates 10 cm , is charged by a DC current. Consider a hypothetical plane surface of area $$A_{\circ}=3.2 cm^{2}$$ inside the capacitor and parallel to the plates. At an instant, the current through the circuit is 6A. At the same instant the displacement current through $$A_{\circ}$$ is ________ mA
correct answer:- 1200
Question 11
A plane electromagnetic wave of frequency 20 MHz travels in free space along the +x direction. At a particular point in space and time, the electric field vector of the wave is $$E_{y}=9.3Vm^{-1}$$. Then, the magnetic field vector of the wave at that point is
correct answer:- 2
Question 12
Arrange the following in the ascending order of wavelength $$ (\lambda) $$ : (A) Microwaves $$ (\lambda_1) $$(B) Ultraviolet rays $$ (\lambda_2) $$ (C) Infrared rays $$ (\lambda_3) $$ (D) X-rays $$ (\lambda_4) $$ Choose the most appropriate answer from the options given below
correct answer:- 4
Question 13
Due to presence of an em-wave whose electric component is given by $$E = 100\sin(\omega t - kx)NC^{-1}$$, a cylinder of length 200 cm holds certain amount of em-energy inside it. If another cylinder of same length but half diameter than previous one holds same amount of em-energy, the magnitude of the electric field of the corresponding em-wave should be modified as
correct answer:- 2
Question 14
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Electromagnetic waves carry energy but not momentum. Reason (R): Mass of a photon is zero. In the light of the above statements, choose the most appropriate answer from the options given below :
correct answer:- 3
Question 15
The electric field of an electromagnetic wave in free space is
$$\vec{E} = 57 \cos \left[ 7.5 \times 10^{6} t - 5 \times 10^{-3} (3x + 4y) \right] (4\hat{i} - 3\hat{j}) N / C$$. The associated magnetic field in Tesla is
correct answer:- 3
Question 16
The magnetic field of an E.M. wave is given by $$\vec{B} = \left(\frac{\sqrt{3}}{2}\,\hat{i} + \frac{1}{2}\,\hat{j}\right) 30 \sin\left[\omega \left(t - \frac{z}{c}\right)\right] \; \text{(S.I. Units)}.$$ corresponding electric field in S.I. units is :
correct answer:- 1
Question 17
A parallel plate capacitor has a capacitance $$C = 200$$ pF. It is connected to $$230$$ V ac supply with an angular frequency $$300$$ rad s$$^{-1}$$. The rms value of conduction current in the circuit and displacement current in the capacitor respectively are :
correct answer:- 4
Question 18
If frequency of electromagnetic wave is 60 MHz and it travels in air along z direction then the corresponding electric and magnetic field vectors will be mutually perpendicular to each other and the wavelength of the wave in m is:
correct answer:- 3
Question 19
A plane electromagnetic wave propagating in $$x$$-direction is described by $$E_y = (200 \text{ V m}^{-1}) \sin[1.5 \times 10^7 t - 0.05x]$$. The intensity of the wave is : (Use $$\epsilon_0 = 8.85 \times 10^{-12} \text{ C}^2 \text{ N}^{-1} \text{ m}^{-2}$$)
correct answer:- 2
Question 20
An object is placed in a medium of refractive index 3. An electromagnetic wave of intensity $$6 \times 10^8$$ W m$$^{-2}$$ falls normally on the object and it is absorbed completely. The radiation pressure on the object would be (speed of light in free space = $$3 \times 10^8$$ m s$$^{-1}$$) :
correct answer:- 3
Question 21
A plane electromagnetic wave of frequency $$35$$ MHz travels in free space along the $$X$$-direction. At a particular point (in space and time) $$\vec{E} = 9.6\hat{j}$$ V m$$^{-1}$$. The value of magnetic field at this point is:
correct answer:- 1
Question 22
The electric field of an electromagnetic wave in free space is represented as $$\vec{E} = E_0 \cos(\omega t - kz)\hat{i}$$. The corresponding magnetic induction vector will be :
correct answer:- 2
Question 23
If the total energy transferred to a surface in time $$t$$ is $$6.48 \times 10^5$$ J, then the magnitude of the total momentum delivered to this surface for complete absorption will be:
correct answer:- 2
Question 24
In a plane EM wave, the electric field oscillates sinusoidally at a frequency of $$5 \times 10^{10}$$ Hz and an amplitude of $$50 \text{ V m}^{-1}$$. The total average energy density of the electromagnetic field of the wave is : [Use $$\varepsilon_0 = 8.85 \times 10^{-12} \text{ C}^2 \text{N}^{-1}\text{m}^{-2}$$]
correct answer:- 1
Question 25
Given below are two statements:
Statement I: Electromagnetic waves carry energy as they travel through space and this energy is equally shared by the electric and magnetic fields.
Statement II: When electromagnetic waves strike a surface, a pressure is exerted on the surface.
In the light of the above statements, choose the most appropriate answer from the options given below:
correct answer:- 2
Question 26
Match List I with List II:

Choose the correct answer from the options given below:
correct answer:- 1
Question 27
Arrange the following in the ascending order of wavelength: A. Gamma rays $$(\lambda_1)$$, B. x-rays $$(\lambda_2)$$, C. Infrared waves $$(\lambda_3)$$, D. Microwaves $$(\lambda_4)$$. Choose the most appropriate answer from the options given below:
correct answer:- 3
Question 28
Match List-I with List-II :

correct answer:- 1
Question 29
The density and breaking stress of a wire are $$6 \times 10^4 \text{ kg/m}^3$$ and $$1.2 \times 10^8 \text{ N/m}^2$$ respectively. The wire is suspended from a rigid support on a planet where acceleration due to gravity is $$\frac{1}{3}^{rd}$$ of the value on the surface of earth. The maximum length of the wire with breaking is ______ m (take, $$g = 10 \text{ m/s}^2$$).
correct answer:- 600
Question 30
Average force exerted on a non-reflecting surface at normal incidence is $$2.4 \times 10^{-4} \text{ N}$$. If $$360 \text{ W/cm}^2$$ is the light energy flux during span of 1 hour 30 minutes, Then the area of the surface is:
correct answer:- 4