| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.39 |
| Score | 0% | 68% |
The pitch of the siren of an approaching ambulance changes as it approaches you. This is an example of which of the following?
sound radiation |
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reflection |
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Doppler effect |
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refraction |
The Doppler effect occurs when the source or listener (or both) of sound waves is moving. If they're moving closer together, the listener perceives the sound with a higher pitch and, when they're moving apart, the listener perceives the sound with a lower pitch.
Small rocks shed by asteroids and comets that reach the earth are called:
meteorites |
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meteoroids |
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shooting stars |
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meteors |
Smaller rocks shed by asteroids and comets are called meteoroids. When these rocks reach Earth's atmosphere, they burn up in the mesosphere and become meteors. If a meteor manages to reach the Earth, it is called a meteorite.
Which of the following is the correct order for types of radiation from longest to shortest wavelength?
infrared waves → microwaves → ultraviolet light |
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microwaves → radio waves → visible light |
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radio waves → visible light → gamma rays |
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visible light → ultraviolet light → radio waves |
The electromagnetic spectrum covers all possible wavelengths and frequencies of radiation. From lowest frequency (longest wavelength) to highest frequency (shortest wavelength) radiation: radio waves → microwaves → infrared waves → visible light → ultraviolet light → X-rays → gamma rays.
These clouds grow upward and can develop into cumulonimbus or thunderstorm clouds.
cumulus clouds |
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stratus clouds |
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cirrus clouds |
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nimbus clouds |
Cumulus clouds are large, puffy, mid-altitude clouds with a flat base and a rounded top. These clouds grow upward and can develop into a cumulonimbus or thunderstorm cloud.
Water freezing or boiling is an example of which of the following?
phase transition |
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heating |
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cooling |
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sublimation |
A substance undergoes a phase transition when it moves from one state of matter to another, for example, when water freezes or boils.