| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.68 |
| Score | 0% | 54% |
Which of the following is not true of light waves?
can travel through a vacuum |
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are mechanical waves |
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travel faster than sound waves |
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are electromagnetic waves |
Unlike mechanical sound waves that require a physical medium for propagation, light waves are electromagnetic and can travel through empty space. Light waves are also much faster, travelling at 186,000 m/s vs. 343 m/s for sound waves.
Atoms of an element whose atoms can vary in the number of neutrons in their nucleus are called which of the following?
isotopes |
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reactants |
|
ions |
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products |
The atomic mass of an element listed in the Periodic Table represents the average mass of a single atom of that element and is measured in atomic mass units (amu). This number is an average as some elements have isotopes with atoms that vary in their number of neturons and, therefore, differ in weight.
Which of the following temperatures is least like the others?
-273°C |
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0K |
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32°F |
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absolute zero |
Absolute zero is the coldest possible temperature in the universe. In the Kelvin scale, absolute zero is 0K and in the Celsius scale it is -273°C.
Examples of secondary consumers include:
plankton |
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chickens |
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grasshoppers |
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wolves |
Secondary consumers (carnivores) subsist mainly on primary consumers. Omnivores are secondary consumers that also eat producers. Examples are rats, fish, and chickens.
Which of the following is the formula for work?
\(W = {F}{d}\) |
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\(W = {\vec{F} \over \vec{d} }\) |
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\(W = \vec{F}\vec{d}\) |
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\(W = {{F}\over{d}}\) |
Work is performed on an object when an applied force causes displacement along the same vector. Measured in joules (J) or newton-meter (Nm), work is calculated by multiplying force times displacement: \(W = \vec{F}\vec{d}\)