List of top Physics Questions on Electromagnetic Spectrum

What are infrared waves ? Why are these waves referred to as ‘heat waves’ ? Give any two uses of these waves.
Name the electromagnetic waves which are used for (i) detection of fractures in bones
(ii) physiotherapy
(iii) radar systems
Also write their wavelength range.
Electromagnetic waves used in a diagnostic tool in medicine have a wavelength range
Name the electromagnetic waves which are used for (i) detection of fractures in bones
(ii) physiotherapy
(iii) radar systems
Also write their wavelength range.
Electromagnetic waves used in a diagnostic tool in medicine have a wavelength range
A radio can tune in to any station in the 7.5 MHz to 12 MHz band. The corresponding wavelength band is
निम्नलिखित विद्युत-चुम्बकीय स्पेक्ट्रम के भागों में उनके संगत मुख्य अनुप्रयोगों को सुमेलित कीजिए :
सही विकल्प है :
The following table presents the part of the electromagnetic spectrum and their corresponding major applications. Match the following and choose the correct option. \[ \begin{array}{|c|c|c|c|} \hline \text{Part of Spectrum} & & \text{Applications} & \\ \hline P & \text{Microwave} & I & \text{For purifying water} \\ \hline Q & \text{UV rays} & II & \text{For warming food} \\ \hline R & \text{Gamma rays} & III & \text{For AM and FM communication systems} \\ \hline S & \text{Radio waves} & IV & \text{Cancer cells treatment} \\ \hline \end{array} \]
The velocity of electromagnetic waves in vacuum is given by
Identify the two electromagnetic waves A and B having respective wavelengths 2 cm and 580 nm
If the force due to sun's radiation on surface area of \(cm^{2}\) is about \(9 \times 10^{-9} N\), then the radiation pressure of the sun's radiation (in \(Nm^{-2}\)) is.
A monochromatic source of light operating at 15 kW emits \(2.5 \times 10^{22}\) photons/s. The region of an electromagnetic spectrum to which the emitted electromagnetic radiation belongs to ________.
A black body has maximum wavelength ' (\lambda_{m}) ' at temperature (2000 K). Its maximum wavelength at (3000 K) will be
The transverse nature of electromagnetic waves is confirmed by the phenomenon of
A \(1\) kW bulb radiates light uniformly in all directions. The intensity at a point on the surface of the surrounding sphere of area \(200\,\text{m}^2\) is (in \(\text{W m}^{-2}\))
A black body has maximum wavelength ' (\lambda_{m}) ' at temperature (2000 K). Its maximum wavelength at (3000 K) will be
An electromagnetic wave travelling in vacuum has its electric field component, $E=15\sin(1.57y+5.4t)\hat{j}$. The wavelength of the wave is:
If \( v_g, v_X \) and \( v_v \) are the speeds of gamma rays, X-rays and visible light respectively in vacuum, then
The vibrations of atoms and molecules produce electromagnetic radiation in the region of
A plane electromagnetic wave with frequency \(40\,\text{MHz}\) travels in free space. At a particular point in space and time, the magnetic field is \(2 \times 10^{-8}\,\text{T}\). What will be the electric field at this point?
The minimum wavelength of Lyman series lines is \( P \), then the maximum wavelength of the Lyman series lines is:
A black body has maximum wavelength ' (\lambda_{m}) ' at temperature (2000 K). Its maximum wavelength at (3000 K) will be
The velocity of light in a medium of relative permittivity 2 and relative permeability 4.5 is (velocity of light in free space is c)
In a plane electromagnetic wave, the magnetic field is given by \(B = 400 \times 10^{-6}\sin[(4.0 \times 10^{-4})(t - x/c)]\). The peak value of electric field (in V m\(^{-1}\)) is
Match List-I with List-II
\[\begin{array}{|l|l|} \hline \text{List-I (Electromagnetic waves)} & \text{List-II (Wavelength range)} \\ \hline \text{(A) X-rays} & \text{(I) 1mm to 700 nm} \\ \hline \text{(B) Radio waves} & \text{(II) 0.1m to 1 mm} \\ \hline \text{(C) Infrared waves} & \text{(III) 1nm to \(10^{-3}\) nm} \\ \hline \text{(D) Microwaves} & \text{(IV) > 0.1 m} \\ \hline \end{array}\]
Choose the correct answer from the options given below: