| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.40 |
| Score | 0% | 68% |
The ozone layer is in which of Earth's atmospheric layers?
troposphere |
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mesosphere |
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thermosphere |
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stratosphere |
The stratosphere is just above the troposphere and is stratified in temperature with warmer layers higher and cooler layers closer to Earth. This increase in temperature is a result of absorption of the Sun's radiation by the ozone layer.
The formula for acceleration is which of the following?
\(\vec{a} = { \vec{F} \over m }\) |
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\(\vec{a} = { m \over F }\) |
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\(\vec{a} = \vec{F} m\) |
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\(\vec{a} = { m \over \vec{F} }\) |
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, \(\vec{F} = m\vec{a}\).
Work is measured in:
horsepower |
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amps |
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joules or newton-meters |
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watts |
Work is performed on an object when an applied force causes displacement along the same vector. Measured in joules (J) or newton-meters (Nm), work is calculated by multiplying force times displacement: \(W = \vec{F}\vec{d}\)
Which of the following is not a medium for sound waves?
vacuum |
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liquid |
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solid |
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none of these is a medium for sound waves |
A vibrating object produces a sound wave that travels outwardly from the object through a medium (any liquid or solid matter). The vibration disturbs the particles in the surrounding medium, those particles disturb the particules next to them, and so on, as the sound propagates away from the vibration.
The respiratory and circulatory systems are similar in that they:
transport oxygen |
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deoxygenate blood |
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add carbon dioxide |
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transport nutrients |
Like the respiratory system, the circulatory system serves to transport oxygen throughout the body while removing carbon dioxide. In addition, the circulatory system transports nutrients from the digestive system.