| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.32 |
| Score | 0% | 66% |
Which of the following is related to the Cambrian Explosion?
carbon dating |
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extinction of dinosaurs |
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first civilizations |
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fossil record |
The Cambrian period is one of the most significant geological time periods. Lasting about 53 million years, it marked a dramatic burst of changes in life on Earth known as the Cambrian Explosion. It is from this period that the majority of the history of life on Earth, as documented by fossils, is found. Called the fossil record, the layering of these mineralized imprints of organisms preserved in sedementary rock have allowed geologists to build a historical record of plant and animal life on Earth.
Which of the following is the formula for work?
\(W = {F}{d}\) |
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\(W = {{F}\over{d}}\) |
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\(W = \vec{F}\vec{d}\) |
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\(W = {\vec{F} \over \vec{d} }\) |
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: \(W = \vec{F}\vec{d}\)
50°F is how many °C?
58 |
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122 |
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10 |
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-10 |
The formula to convert from F° to C° is:
\(C° = {5 \over 9} (F° - 32)\)
plugging in our values gives:
\(C° = {5 \over 9} (50 - 32)\)
\(C° = {5 \over 9} (18)\)
\(C° = {90 \over 9}\)
\(C° = 10\)
The envelope of gases surrounding the planet is called the:
hydrosphere |
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geosphere |
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lithosphere |
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atmosphere |
The biosphere is the global ecological system integrating all living beings and their relationships. This includes their interactions with the lithosphere (the rigid outer part of the earth, consisting of the crust and upper mantle), hydrosphere (all surface water), and atmosphere (the envelope of gases surrounding the planet).
Materials like metals that transfer heat efficiently are called:
insulators |
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reflectors |
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conductors |
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refractors |
Heat is always transferred from warmer to cooler environments and conduction is the simplest way this transfer can occur. It is accomplished through direct contact between materials and materials like metals that transfer heat efficiently are called conductors while those that conduct heat poorly, such as plastic, are called insulators.