| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.21 |
| Score | 0% | 64% |
Which of the following describes how a person's genes express themselves in physical characteristics?
chromotype |
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DNA |
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phenotype |
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genotype |
A person's genotype is their genetic makeup and includes both dominant and recessive alleles. Phenotype is how the genes express themselves in physical characteristics.
Acceleration is the rate of change of velocity per unit of time. Which of these is the formula for acceleration?
\(\vec{a} = { \Delta \vec{v} \over t }\) |
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\(\vec{a} = \Delta \vec{v} t \) |
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\(\vec{a} = { \vec{v} \over t }\) |
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\(\vec{a} = { t \over \Delta \vec{v} }\) |
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 \(\vec{a} = { \Delta \vec{v} \over t }\)
"An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force." This describes which of Newton's laws of motion?
second |
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first |
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fourth |
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third |
Also known as the law of inertia, Newton's first law of motion states that An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
An element in the physical state of __________ maintains neither a constant volume nor a constant shape.
gas |
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liquid |
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plasma |
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solid |
The gaseous state occurs at a higher temperature range than the solid and liquid states of the same substance. In this state, molecules flow very freely around each other and will spread out as far as they're able. Gases maintain neither a constant volume nor a constant shape.
The coldest point in the Earth's atmosphere is reached in which atmospheric layer?
mesosphere |
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stratosphere |
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troposphere |
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thermosphere |
In the mesosphere, temperature again drops as altitude increases until the coldest point in the Earth's atmosphere, the mesopause, is reached where temperatures fall to −225 °F (−143 °C).