| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.24 |
| Score | 0% | 65% |
Which of the following is not true about mass and weight?
weight is the force exerted on an object by gravity |
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mass depends on the location where it is measured |
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mass is the amount of matter something has |
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weight depends on the location where it is measured |
Mass is the amount of matter something has while weight is the force exerted on an object's mass by gravity. So, although a person's mass doesn't change when going from the Earth to the Moon, their weight will decrease because the force of the Moon's gravity is much less than that of Earth.
Convert 0C° to F°.
0 |
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16 |
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32 |
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-32 |
To convert from C° to F° use:
\(F° = {9 \over 5}C° + 32\)
\(F° = {9 \over 5}(0) + 32\)
\(F° = 0 + 32 = 32\)
pH is a scale that measures of how basic or acidic a solution is. A solution with a pH of 4 is:
acidic |
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alkaline |
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basic |
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neutral |
An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.
The heart __________ blood.
oxygenates |
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filters |
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creates |
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deoxygenates |
To provide oxygen to the body, blood flows through the heart in a path formed by the right atrium → right ventricle → lungs → left atrium → left ventricle → body. When blood enters the right side of the heart it is deoxygenated. It enters the left side of the heart oxygenated after traveling to the lungs.
Arteries carry __________ blood at __________ pressure.
oxygenated, high |
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deoxygenated, high |
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deoxygenated, low |
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oxygenated, low |
Veins carry blood back to the heart from the body. While arteries are thick-walled because they carry oxygenated blood at high pressure, veins are comparatively thin-walled as they carry low-pressure deoxygenated blood. Like the heart, veins contain valves to prevent blood backflow.