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The Doppler effect is used in radar to provide information regarding the speed of moving targets by measuring the frequency shift between the emitted and the reflected radiation. A transmitter produces pulsed radio frequency radiation. It is fed to a movable aerial from which it is transmitted as a beam. When the beam strikes the moving vehicle a part of the energy of the radiation is reflected back to the aerial. Signals received by the aerial are passed to the receiver, where they are amplified and detected. There will be a shift in frequency of the reflected wave and emitted wave due to the Doppler effect. The apparent frequency of the reflected wave is given by
F = f ( 1 - v/c ) where v is the speed at which the source and the observer are moving apart and c is the speed of electromagnetic radiation, f is the real frequency or the frequency of the emitted signal
The output of the detector is usually displayed on a cathode ray tube. The apparent frequency is measured and thus the speed of the vehicle is calculated.
A heterodyne device may also be used in which beats are produced by superimposing the emitted radio wave over the reflected (from the vehicle) radio wave. In the heterodyne wave meter, a variable frequency local oscillator is adjusted to give predetermined beat frequency with the incoming reflected wave, enabling the frequency of the reflected wave which has had Doppler shift to be determined. Thus the speed of the vehicle can be determined.
What else can I help you with?
What are the different types of ultrasonic waves?
There are mainly two types of ultrasonic waves: longitudinal waves and shear waves. Longitudinal waves produce compressions and rarefactions in the medium along the direction of wave propagation, while shear waves produce perpendicular oscillations to the direction of wave propagation. Longitudinal waves are commonly used in medical imaging applications like ultrasound scans, while shear waves are used in non-destructive testing of materials to detect internal defects.
Are sound waves transverse waves while light waves are longitudinal waves or are all sound waves and light waves longitudinal waves?
Sound waves are longitudinal waves, where the particles of the medium vibrate parallel to the direction of the wave. Light waves, on the other hand, are transverse waves, where the oscillation is perpendicular to the direction of wave travel.
Are light waves transverse waves or longitudinal waves?
Light waves are transverse waves. This means that the oscillation of the wave is perpendicular to the direction of energy propagation.
What waves arent transverse?
Longitudinal waves are not transverse. In longitudinal waves, the particles of the medium move parallel to the direction of the wave propagation instead of perpendicular to it like in transverse waves. Sound waves are an example of longitudinal waves.
What statement best describes longitudinal waves?
Longitudinal waves are mechanical waves in which the particles of the medium vibrate in the same direction as the wave's energy propagation. Examples of longitudinal waves include sound waves and seismic waves.
Are p waves transverse waves or longitudinal waves?
P-waves are longitudinal and S-waves are transverse waves.
Are sound waves longitudinal in solids?
No Sound waves are longitudinal. Being longitudinal they cannot be POLARISED.
Are P-waves and S-waves transverse or longitudinal waves?
P-waves are longitudinal and S-waves are transverse waves.
What are two types of mechanical waves?
transverse and longitudinal
Are soundwaves longitudinal waves?
longitudinal wave
What are the different types of ultrasonic waves?
There are mainly two types of ultrasonic waves: longitudinal waves and shear waves. Longitudinal waves produce compressions and rarefactions in the medium along the direction of wave propagation, while shear waves produce perpendicular oscillations to the direction of wave propagation. Longitudinal waves are commonly used in medical imaging applications like ultrasound scans, while shear waves are used in non-destructive testing of materials to detect internal defects.
How are longitudinal waves used in communication?
All sound waves are longitudinal (compression/rarefaction) waves.
Are sound waves transverse waves while light waves are longitudinal waves or are all sound waves and light waves longitudinal waves?
Sound waves are longitudinal waves, where the particles of the medium vibrate parallel to the direction of the wave. Light waves, on the other hand, are transverse waves, where the oscillation is perpendicular to the direction of wave travel.
Are light waves transverse waves or longitudinal waves?
Light waves are transverse waves. This means that the oscillation of the wave is perpendicular to the direction of energy propagation.
What waves arent transverse?
Longitudinal waves are not transverse. In longitudinal waves, the particles of the medium move parallel to the direction of the wave propagation instead of perpendicular to it like in transverse waves. Sound waves are an example of longitudinal waves.
What statement best describes longitudinal waves?
Longitudinal waves are mechanical waves in which the particles of the medium vibrate in the same direction as the wave's energy propagation. Examples of longitudinal waves include sound waves and seismic waves.
Is a sound wave a transverse wave or longitudinal wave?
Sound waves are longitudinal.
