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Is there any Doppler effect of sound when the observer or source moves at right angles to the lines joining them?
Wiki User
∙ 15y ago
No. At right angles, there is no wavefront compression or expansion to cause a Doppler shift. However, the only way to move at perpetual right angles is when the source moves on a circle (or sphere) about the observer (or vice versa). What is more common is something like when a train whistle (source) passes by a station (observer) at constant speed; in this case, the direction of motion and line-of-sight are only at right angles for the moment that the train whistle is directly in front of the station. At that moment, there is no Doppler shift. But before or after that moment, there is a decreasing or increasing Doppler shift as more or less of the motion is perpendicular to the line-of-sight, respectively. To understand the concept of wavefront compression, imagine you're throwing a Basketball at a person walking toward you. Pretend the basketball always moves at the same speed, and pretend the only way it can change direction is by bouncing off of something. The first time it bounces and comes back in 2 minutes. You do it again, and the second time it bounces and comes back in 1 minute and 50 seconds. That is because the distance between you and the person has been compressed by his/her motion. When a sound wave (or radio wave or light wave) is compressed, it changes frequency. If the person is walking in a circle, the distance is never compressed - by definition all points on a circle/sphere are equi-distant from the center. I'm a radar engineer and Doppler effect is a significant part of my job.
Wiki User
∙ 15y ago
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Why do the tangents drawn at the ends of a chord of a circle make equal angles with the chord?
Because in effect an isosceles triangle has been constructed and the base angles are always equal.
Can two shapes be congruent and not similar?
In short, no. Similar shapes are shapes in which all corresponding angles congruent regardless of the length of the sides. Congruent shapes have congruent corresponding angles and corresponding sides. In effect congruent shapes is a special condition of similar shapes.
How does speed affect the frequency of reflected waves?
The Doppler Effect describes a frequency shift in reflected waves in proportion to the relative speed between the receiver and the reflected object. For instance, in a radar speed trap, the frequency shift in reflected radio waves allows the unit to calculate the speed toward (higher frequency) or away from (lower frequency) the transmitter/receiver unit. When you drive past a steady noise source, such a bell or a horn, the sound has a higher frequency as you approach and a lower frequency as you depart.
An important statistical effect was named for this manufacturing plant What is it?
hawthorne effect
Is cause and effect and verb or adjective?
In the term 'cause and effect', the words 'cause' and 'effect' are nouns, joined by the conjunction 'and'; they are singular, common, abstract nouns.The term 'cause and effect' can be used as a compound subject of a sentence or clause and the compound object of a verb or a preposition. Examples:The cause and effect are obvious in retrospect.You must consider the cause and effect before you decide to act.The word cause is also a verb: cause, causes, causing, caused.The word effect is also a verb: effect, effects, effecting, effected.
A detected apparent change in the pitch caused by the motion of a sound source or of an observer is called?
The Doppler effect.The Doppler effect.The Doppler effect.The Doppler effect.
Is the Doppler effect the same as a reflected wave?
No. The Doppler effect is an apparent change in frequency, due to movement, away from towards the observer.
The shifting of lightwaves as an object moves away from the observer is what?
The Doppler effect
Why doesn't the Doppler shift appear when an observer moves toward the source?
Doppler's effect does not happen when the observer is moving towards the source because unlike the source when observer moves forward the waves are not compressed and they pass the observer without being compressed and since the doppler effect is due to the Change in wavelength of the wave, it fails to occur.
Is the Doppler effect the actual change in a stars frequency of a wave?
No. Doppler effect measures relative speed toward or away from the observer, there is no effect on the star itself.
What is the Doppler effect on sound?
The Doppler effect is a phenomenon observed whenever the source of waves is moving with respect to an observer. The Doppler effect can be described as the effect produced by a moving source of waves in which there is an apparent upward shift in frequency for the observer and the source are approaching and an apparent downward shift in frequency when the observer and the source is receding. The Doppler effect can be observed to occur with all types of waves - most notably water waves, sound waves, and light waves.
When a sound source is moving away from an observer the observer will hear a lower pitch. This is due to?
This is due to the Doppler effect.
Does the Doppler effect happen with light?
Yes, the Doppler effect can be applied to light. Any wave function can be subject to the Doppler effect if there is relative motion between the source and an observer. That's how we know that the Universe is expanding.
How can the Doppler effect help us?
By determining the speed of an object, towards or away from the observer.
What is dopper effect?
The Doppler effect is a change of the frequencey of a wave, due to relative movement between source and observer.
Does the Doppler Effect occur when both the source and observer are moving at the same velocity?
No. There has to be a relative velocity.
What is dopler effect?
Doppler effect refers to a decrease in the frequency of waves as the observer or the source moves away from each other.
