| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.44 |
| Score | 0% | 69% |
Changes to an object's speed or direction of motion are caused by which of the following?
power |
|
a force |
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kinetic energy |
|
work |
Force is applied to change an object's speed or direction of motion.
The rate of vibration of sound is called:
amplitude |
|
volume |
|
period |
|
frequency |
The rate of vibration of sound is called frequency and is measured in hertz (Hz). One hertz is one repetition per second and sounds with high frequency have a higher pitch than sounds with lower frequency. Humans can hear sounds in the range of 20 Hz to 20 kHz.
Heredity is the passing on of physical or mental characteristics genetically from one __________ to another.
family |
|
cell |
|
species |
|
generation |
Heredity is the passing on of physical or mental characteristics genetically from one generation to another. Heredity is made possible via large strings of chromosomes which carry information encoded in genes.
Sound travels fastest through which of the following media?
vacuum |
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air |
|
water |
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metal |
The speed of a sound wave will vary with the medium. Sound travels fastest through media that has particles that are very close together, like metal. Thus, it travels faster through water than through air and doesn't travel at all through a vacuum (there are no particles in empty space to vibrate).
Respiration is the process by which __________ absorb oxygen and eliminate carbon dioxide.
capillaries |
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diaphragms |
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bronchioles |
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blood cells |
The respiratory system manages respiration which is the process by which blood cells absorb oxygen and eliminate carbon dioxide.