| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.27 |
| Score | 0% | 65% |
Which of Earth's layers has weather?
stratosphere |
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mesosphere |
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troposphere |
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thermosphere |
The Earth's atmosphere has several layers starting with the troposphere which is closest in proximity to the surface. Containing most of the Earth's breathable air (oxygen and nitrogen), it's a region with warmer temperatures closer to the surface and cooler temperatures farther away which results in the rising and falling air that generates weather.
The Sun is a __________-type main-sequence star.
D |
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S |
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G |
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E |
The Sun is a G-type main-sequence star (G2V) but is informally known as a yellow dwarf star. Composed of 73% hydrogen and 25% helium, the hot plasma that makes up the Sun reaches 9,900°F (5,505°C) at the surface. It formed approximately 4.6 billion years ago and makes up 99.86% of the mass in the solar system.
The pitch of the siren of an approaching ambulance changes as it approaches you. This is an example of which of the following?
refraction |
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Doppler effect |
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reflection |
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sound radiation |
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.
50°F is how many °C?
58 |
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122 |
|
-10 |
|
10 |
The formula to convert from F° to C° is:
\(C° = {5 \over 9} (F° - 32)\)
plugging in our values gives:
\(C° = {5 \over 9} (50 - 32)\)
\(C° = {5 \over 9} (18)\)
\(C° = {90 \over 9}\)
\(C° = 10\)
Force is measured in newtons (N) with 1 N being the force required to impart an acceleration of:
1 m/s to a mass of 1 kg |
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1 m/s2 to a mass of 1 kg/s2 |
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1 m/s2 to a mass of 1 kg |
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1 mph to a mass of 1 kg |
Weight is a force that describes the attraction of gravity on an object. Force is measured in newtons (N) with 1 N being the force required to impart an acceleration of 1 m/s2 to a mass of 1 kg.