| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.99 |
| Score | 0% | 60% |
Which of the following describes the Earth's outer core?
liquid |
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makes up most of the Earth's volume |
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primarily solid |
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solid |
The Earth's core is divided into the liquid outer core (1,430 miles or 2,300 km radius) and the solid inner core (745 miles or 1,200 km radius).
In the metric system, what prefix represents 103?
centi |
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kilo |
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mega |
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milli |
Kilo is the metric system prefix for 103.
Which of Earth's layers has weather?
stratosphere |
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troposphere |
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thermosphere |
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mesosphere |
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.
Vector quantities are fully described by which of the following?
a magnitude and a direction |
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a magnitude only |
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a direction and a polarity |
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a direction only |
Velocity and displacement are vector quantities which means each is fully described by both a magnitude and a direction. In contrast, scalar quantities are quantities that are fully described by a magnitude only. A variable indicating a vector quantity will often be shown with an arrow symbol: \(\vec{v}\)
The formula for acceleration is which of the following?
\(\vec{a} = { \vec{F} \over m }\) |
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\(\vec{a} = { m \over \vec{F} }\) |
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\(\vec{a} = { m \over F }\) |
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\(\vec{a} = \vec{F} m\) |
Newton's second law of motion leads to the formula for acceleration which is a measure of the rate of change of velocity per unit time and, if you solve for positive acceleration, reveals how much net force is needed to overcome an object's mass. The formula for acceleration is \(\vec{a} = { \vec{F} \over m }\) or, solving for force, \(\vec{F} = m\vec{a}\).