Description : What factor determines whether a radio wave is reflected or refracted by the ionosphere?
Last Answer : Thickness of ionized layer.
Description : The layer of the atmosphere in which Radio Waves are reflected back is called- (1) Ionosphere (2) Troposphere (3) Stratosphere (4) Exosphere
Last Answer : (1) Ionosphere Explanation: The Radio waves are reflected back to Earth in the Ionosphere which is an electrically charged layer of the upper atmosphere. This process is used to communicate beyond the horizon, atintercontinental distances, mostly in the shortwave frequency bands.
Description : In radio-communication, the signals emitted by transmitting antenna are reflected on – (1) stratosphere (2) ozonosphere (3) ionosphere (4) troposphere
Last Answer : (3) ionosphere Explanation: The lower atmosphere is more or less transparent to radio waves. However, the ionosphere reflects back the radio waves. Thus, a signal emitted by an antenna from a ... on the surface of Earth in the following two ways: ground wave propagation and sky wave propagation.
Description : In radio-communication, the signals emitted by transmitting antenna are reflected on (1) stratosphere(2) ozonosphere (3) ionosphere (4) troposphere
Last Answer : ionosphere
Description : The layer of the atmosphere in which Radio Waves are reflected back is called ; (1) Ionosphere (2) Troposphere (3) Stratosphere(4) Exosphere
Last Answer : Ionosphere
Description : The rhombic antenna is primarily used for A. ground wave propagation B. space wave propagation C. ionosphere scatter propagation D. sky wave propagation
Last Answer : D. sky wave propagation
Description : Which of the following layers of the ionosphere has no effect on sky wave propagation during daytime? A. D B. E C. F1 D. F2
Last Answer : A. D
Description : What is a selective fading effect? A. A fading effect caused by small changes in beam heading at the receiving station. B. A fading effect caused by phase differences between radio wave ... station D. A fading effect caused by time differences between the receiving and transmitting stations.
Last Answer : B. A fading effect caused by phase differences between radio wave components of the same transmission, as experienced at the receiving station.
Description : Which if the following layers of the ionosphere has no effect on sky wave propagation during the hours of darkness? A. D B. E C. F1 D. F2
Description : What is the major cause of selective fading? A. Small changes in the beam heading at the receiving station. B. Large changes in the height of the ionosphere, as experience at the ... Phase differences between radio wave components of the same transmission, as experienced at the receiving station.
Last Answer : D. Phase differences between radio wave components of the same transmission, as experienced at the receiving station.
Description : Refers to an effect of selective fading. A. A fading effect caused by phase differences between radio wave components of the same transmission, as experienced at the receiving station. B. A fading ... caused by large changes in the height of the ionosphere, as experienced at the receiving station.
Last Answer : A. A fading effect caused by phase differences between radio wave components of the same transmission, as experienced at the receiving station.
Description : A 'body' which allows the short wavelength incoming solar radiation to enter in, but does not allow long wave length outgoing infra red radiation to escape out is called the (A) Global warming (B) Green house (C) Atmospheric effect (D) Ionosphere
Last Answer : (B) Green house
Description : Describe the effect of ionosphere on sky wave propagation.
Last Answer : The Ionosphere is the upper portion of the atmosphere. The ultra violet radiation from the sun will ionize the upper layer of the atmosphere. In this layer free electrons and positive and negative ions are ... layer. Its Frequency Range is from 3 MHz to 30 MHz Polarization: Vertical.
Description : The layer of atmosphere used for radio-wave transmission is (1) chromosphere (2) troposphere (3) ionosphere (4) stratosphere
Last Answer : The velocity of the wave as it passes from air into ionosphere Increases.
Description : A sound wave that is reflected back toward the source is known as what type of sound?
Last Answer : Echo.
Description : The sinusoidal wave `y(x,t) = ym sin(kx-omegat)` is incident on the fixed end of a string at `x = L`. The reflected wave is given by :-
Last Answer : The sinusoidal wave `y(x,t) = ym sin(kx-omegat)` is incident on the fixed end of a string at `x = L` ... (kx+omegat-kL)` D. `y_(m)sin(kx+omegat-2kL)`
Description : When a light wave is reflected from a mirror, there is a change in its
Last Answer : Amplitude
Description : When a light wave is reflected from a mirror, there is a change in its – (1) frequency (2) amplitude (3) wavelength (4) velocity
Last Answer : (2) amplitude Explanation: When a light wave is reflected from an object, it changes not only its amplitude but also its phase according to the properties of the object at a particular point. The velocity and momentum are just reversed in another direction.
Description : When electromagnetic wave are propagated through a waveguide, they A. are reflected from the walls but do not travel along them B. travel along all four walls of the waveguide C. travel along the broader walls of the guide D. travel through the dielectric without touching the walls
Last Answer : A. are reflected from the walls but do not travel along them
Description : Find the reflection coefficient of a wave with an incident electric field of 5 units and reflected electric field of 2 units. a) 2.5 b) 0.4 c) 0.8 d) 1.2
Last Answer : b) 0.4
Description : Find the permittivity of the surface when a wave incident at an angle 60 is reflected by the surface at 45 in air. a) 1.41 b) 3.5 c) 2.2 d) 1.73
Last Answer : d) 1.73
Description : A wave incident on a surface at an angle 60 degree is having field intensity of 6 units. The reflected wave is at an angle of 30 degree. Find the field intensity after reflection. a) 9.4 b) 8.4 c) 10.4 d) 7.4
Last Answer : c) 10.4
Description : An Electromagnetic wave falls on to a boundary between two losses less homogeneous media with different refractive indices, a part of the wave is reflected back to the incident medium and the rest is transmitted ... A) Fresnel reflection (B) Fresnel refraction (C) Snell's law (D) None of these
Last Answer : Answer: Option A
Description : When a light wave is reflected from a mirror, there is a change in its?
Description : When a wave strikes a vertical breakwater in deep water, it is reflected back and on meeting another advancing wave of similar amplitude merges and rises vertically in a wall of water. This phenomenon is called (A) Surf (B) Clapotis (C) Fetch (D) Swell
Last Answer : (B) Clapotis
Description : When a wave is reflected from a surface, energy is transferred. When is the transfer of energy greatest?
Last Answer : When the incident wave is nearly parallel with the surface.
Description : A light wave enters a sheet of glass at a perfect right angle to the surface. Is the majority of the wave reflected, refracted, transmitted, or absorbed?
Last Answer : Transmitted.
Description : When a wave is reflected from a surface, energy is reflected. When is the reflection of energy the greatest?
Last Answer : When the wave is nearly parallel to the reflecting surface.
Description : When a light wave suffers reflection at the interface between air and glass medium, the change of wavelength of the reflected wave in air is equal to (a) 0 (b) λ/2 (c) λ (d) 2λ
Last Answer : (b) λ/2
Description : When a light wave suffers reflection at the interface between air and glass medium, the change of phase of the reflected wave in air is equal to (a) 0 (b) π (c) 2π (d) π/2
Last Answer : (b) π
Description : When a light wave suffers reflection at the interface between air and glass medium, the change of phase of the reflected wave in air is equal to A. 0 B. π C.2 π D.π /2
Last Answer : B. π
Description : When a light wave is reflected from a mirror, there is a change in its (1) frequency (2) amplitude (3) wavelength (4) velocity
Last Answer : amplitude
Description : In which type of waves is the motion of the particles perpendicular to the direction of the wave is traveling?
Last Answer : transverse waves
Description : What causes the maximum usable frequency to vary? A. The temperature of the ionosphere B. The speed of the winds in the upper atmosphere C. The type of weather just below the ionosphere D. The amount of radiation received from the sun
Last Answer : D. The amount of radiation received from the sun
Description : VLFwaves are used forsome type ofservices because a. of the low powers required b. the transmitting antennas are of convenient size c. they are very reliable d. the penetrate the ionosphere easily
Last Answer : c. they are very reliable
Description : What are Waves that move the particles of the wave parallel to the direction the waves are traveling are called?
Last Answer : the distance between two corresponding parts of a wave is a waves
Description : Two particles of of a medium disturbed by the wave propagation are at `x_(1) = 0` and `x_(2) = 1 cm`. The wave is propagating in positive x-direction.
Last Answer : Two particles of of a medium disturbed by the wave propagation are at `x_(1) = 0` and `x_(2) = 1 cm`. The ... `y = (2) sin [(2pi)/(16)(24t-x)]cm`.
Description : In a compression wave do particles in the medium move?
Last Answer : Need answer
Description : In a compression or longitudinal wave the particles of the medium are displaced in a direction to the direction of energy transport.?
Last Answer : Feel Free to Answer
Description : How a water wave passes the particles that make up the water move?
Description : (2) Exclusion Principle of Pauli Explanation: The Pauli exclusion principle is the quantum mechanical principle that no two identical fermions (particles with half-integer spin) may occupy the same ... function for two identical fermions is anti-symmetric with respect to exchange of the particles.
Last Answer : The three elements most needed in common fertilizers are – (1) Sulphur, Phosphorous and Sodium (2) Nitrogen, Phosphorous and Sodium (3) Phosphorous, Sodium and Nitrogen (4) Calcium, Phosphorous and Potassium
Description : Which of the following particles has the dual nature of particle-wave? (1) Electron (2) Meson (3) Proton (4) Neutron
Last Answer : (1) Electron
Description : Which theory states that the light wave behaves as if it consists of many tiny particles? a. Huygen’s theory b. Wave theory of light c. Nyquist theory d. Quantum theory
Last Answer : d. Quantum theory
Description : In a longitudinal wave, the vibration of particles and the direction of wave are in
Last Answer : the same direction.
Description : The waves in which particles vibrate in the direction perpendicular to the direction of wave propagation are called
Last Answer : transverse waves.
Description : Do the particles of the medium in which a wave moves travel along with the wave? Explain with an example.
Last Answer : When a wave propagates in a medium, the particles of the medium vibrate about their mean position and the energy is transferred without transfer of the particles of the medium. For example: Take some water ... cork in it. When the water is disturbed, the cork moves up and down but not forward.
Description : How is the energy transferred in a wave without transfer of particles of the medium?
Last Answer : When a wave propagates in a medium, the particles of the medium vibrate about their mean position and the energy is transferred without the transfer of particles of the medium.
Description : Pick up the incorrect statement from the following: (A) As a wave of sea water approaches the coast line, it is generally accompanied by a drift of water in the direction of wave advance (B) ... in the direction of the wave (D) The wave while receding carries finer particles out to deep water
Last Answer : (C) A falling hydraulic gradient occurs in the direction of the wave
Description : Which theory states that the light wave behaves as if it consists of many tiny particles? ∙ a. Huygen’s theory ∙ b. Wave theory of light ∙ c. Nyquist theory ∙ d. Quantum theory
Last Answer : ∙ d. Quantum theory