| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.88 |
| Score | 0% | 58% |
In the metric system, what prefix represents 10-3?
milli |
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centi |
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mega |
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kilo |
In the metric system, milli is the prefix for 10-3.
Acceleration is the rate of change of velocity per unit of time. Which of these is the formula for acceleration?
\(\vec{a} = { \vec{v} \over t }\) |
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\(\vec{a} = \Delta \vec{v} t \) |
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\(\vec{a} = { t \over \Delta \vec{v} }\) |
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\(\vec{a} = { \Delta \vec{v} \over t }\) |
Acceleration is the rate of change of velocity per unit of time. In physics, the delta symbol (\(\Delta\)) represents change so the formula for acceleration becomes \(\vec{a} = { \Delta \vec{v} \over t }\)
Which of the following is not a medium for sound waves?
vacuum |
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liquid |
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none of these is a medium for sound waves |
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solid |
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.
In the foood chain, producers serve as a food source for other organisms. Typical producers are plants that can make their own food through photosynthesis and certain bacteria that are capable of converting inorganic substances into food through:
chemosynthesis |
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decomposition |
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photosynthesis |
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autotrophs |
Producers (autotrophs) serve as a food source for other organisms. Typical producers are plants that can make their own food through photosynthesis and certain bacteria that are capable of converting inorganic substances into food through chemosynthesis
The transfer of heat by the circulation or movement of the heated parts of a liquid or gas is called:
convection |
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radiation |
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conduction |
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diffusion |
Convection is the transfer of heat by the circulation or movement of the heated parts of a liquid or gas. Examples of heat transfer by convection include water coming to a boil on a stove, ice melting, and steam from a cup of coffee.