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Our eyes respond to wavelength ranging from
The human eye is sensitive to light in the wavelength range of approximately 400 nm (violet) to 700 nm (red). This range is known as the visible spectrum.
In microwave oven, we use electromagnetic oscillators which produce electro- magnetic waves in the wavelength range
What is the direction of $ \vec E \times \vec B $ in an electromagnetic wave ?
In an electromagnetic wave, the direction of the cross product $ \vec{E} \times \vec{B} $ is the direction of propagation of the wave. This follows from the right-hand rule in vector mathematics.
The wavelength of x rays is of the order of
X-rays have wavelengths in the range of 0.01 to 10 nanometers, which corresponds to 0.1 to 100 angstroms. Therefore, the wavelength of X-rays is of the order of 1 angstrom.
A plane electromagnetic wave of frequency 25MHz travels in free space along the x direction. At a particular point in space and time $ \vec E = 6.3 \hat j Vm^{-1} $ then $ \vec B $ at this point is
For a plane electromagnetic wave traveling in free space, the relationship between the electric field (E) and magnetic field (B) is given by the equation \( B = \frac{E}{c} \), where \( c \) is the speed of light (\( 3 \times 10^8 \) m/s). Given \( E = 6.3 \) V/m, we find \( B = \frac{6.3}{3 \times 10^8} = 2.1 \times 10^{-8} \) T. Since the wave is traveling along the x-direction and \( \vec{E} \) is along the y-direction, \( \vec{B} \) must be along the z-direction (\( \hat{k} \)). Thus, \( \vec{B} = 2.1 \times 10^{-8} \hat{k} \) T.
Energy density of an electromagnetic wave of intensity $0.02 Wm^{-2}$ is
The waves used in communication are generally called
The waves used in communication are typically radio waves. These waves have the appropriate wavelength and frequency to travel long distances and penetrate through obstacles, making them ideal for communication purposes. $ ext{Radio waves}$ are used in various communication technologies like television, radio broadcasting, and cell phones.
In an electromagnetic wave, if the amplitude of magnetic field is $ 3 \times 10 ^ {-10 } T $ amplitude of the associated electric field will be
In an electromagnetic wave, the relationship between the electric field $(E)$ and the magnetic field $(B)$ is given by $E = cB$, where $c$ is the speed of light in a vacuum $(3 imes 10^8 ext{ m/s})$. Given $B = 3 imes 10^{-10} ext{ T}$, the amplitude of the associated electric field will be $E = 3 imes 10^8 ext{ m/s} imes 3 imes 10^{-10} ext{ T} = 9 imes 10^{-2} ext{ Vm}^{-1}$. Therefore, the correct option is $9 imes 10^{-2} ext{ Vm}^{-1}$.
The electric and magnetic field of an electromagnetic wave are
In an electromagnetic wave, the electric field $( ext{E})$ and the magnetic field $( ext{B})$ are in phase and perpendicular to each other. This means that both fields reach their maximum and minimum values at the same points in space and time, and they are oriented at right angles to each other. This orthogonal relationship is a fundamental characteristic of electromagnetic waves.
The dimensions of $ { 1 \over \mu \varepsilon } $ are
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The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.