| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.22 |
| Score | 0% | 64% |
Food is mixed with gastric acid and pepsin in the __________ to help break down protein.
small intestine |
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large intestine |
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stomach |
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mouth |
Food is mixed with gastric acid and pepsin in the stomach to help break down protein.
In the Periodic Table of the Elements, atomic number is equal to which of the following?
number of neutrons in the nucleus |
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number of electrons orbiting the nucleus |
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number of protons + neutrons in the nucleus |
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number of protons in the nucleus |
The Periodic Table of the Elements categorizes elements primarily by the number of protons in their nucleus (atomic number) and secondarily by the characteristics they exhibit.
The pitch of the siren of an approaching ambulance changes as it approaches you. This is an example of which of the following?
Doppler effect |
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sound radiation |
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refraction |
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reflection |
The Doppler effect occurs when the source or listener (or both) of sound waves is moving. If they're moving closer together, the listener perceives the sound with a higher pitch and, when they're moving apart, the listener perceives the sound with a lower pitch.
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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weight depends on the location where it is measured |
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mass is the amount of matter something has |
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mass 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.
Which of the following would you find in the side view mirror of a car?
concave lens |
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convex lens |
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convex mirror |
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concave mirror |
A concave (or converging) mirror bulges inward and focuses reflected light on the mirror's focal point where the mirror's angles of incidence converge. In contrast, a convex (or diverging) mirror bulges outward and diffuses the light waves that strike it. A common use of a concave mirror is in a reflecting telescope, a common use of a convex mirror is in the side view mirror of a car.