| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.09 |
| Score | 0% | 62% |
Water has a refractive index of 1.33. Which of the following is true?
light is 1.33 times dimmer in a vacuum than it is in water |
|
light travels 1.33 times faster in a vacuum than it does in water |
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light is 1.33 times brighter in a vacuum than it is in water |
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light travels 1.33 times slower in a vacuum than it does in water |
The speed of light varies based on the material that the waves are passing through. The refractive index of a material indicates how easily light travels through it compared to how easily light travels through a vacuum. For example, the refractive index of water is 1.33, meaning that light travels 1.33 times faster in a vacuum than it does in water.
In the food chain, omnivores may be which of the following?
primary or tertiary consumers |
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secondary consumers or scavengers |
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secondary or tertiary consumers |
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primary or secondary consumers |
Secondary or tertiary consumers may be omnivores.
Changes to an object's speed or direction of motion are caused by which of the following?
kinetic energy |
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work |
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power |
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a force |
Force is applied to change an object's speed or direction of motion.
The coldest point in the Earth's atmosphere is reached in which atmospheric layer?
troposphere |
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thermosphere |
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stratosphere |
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mesosphere |
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).
Gametes have how many pairs of chromosomes?
23 |
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46 |
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2 |
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4 |
Reproductive (haploid) cells known as gametes have half as many (23) pairs of chromosomes as normal (diploid) cells. When the male gamete (sperm) combines with the female gamete (ovum) through meiosis to form a zygote, each gamete supplies half the chromosomes needed to form the normal diploid cells.