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What best describes the most widely accepted theory of the system's evolution?
Astronomers theorize that the solar system formed from a cloud of gas and dust that contracted under its own gravity and began to spin. Most of the cloud gravitated toward the center of this spinning disk, forming the sun. Smaller amounts of matter spun in separate eddies, creating nuclei around which evolving planetesimals formed.
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What does the Hertzsprung-Russel diagram do?
Plots the luminosity of stars as function of their surface temperature. The luminosity increases upward on the vertical axis, while the temp decreases.
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Regional metamorphism, in which large areas covering hundreds of miles are affected, is believed to be primarily the result of...
horizontal stresses associated with convergent plate boundaries.
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Describe the changes in the contour and form of the beach
In general, the stronger the wave action on a beach, the steeper the beach profile. From April thru Sept small waves permit the deposit of sand. Oct to March large waves of winter storms erode the sand
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When groundwater is pumped from an unconfined sand-and-gravel aquifer, sometimes the amount of groundwater withdrawn exceeds the recharge of the aquifer. What is the most likely consequence of withdrawing more water from this kind of aquifer than is naturally recharged?
The water table will be lowered, and water from streams, lakes, and wetlands will move downward into the aquifer in response to the decrease in groundwater elevation.
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A convergent lens is used to create an image of an arrow. If the focal length of the lens is 0.1 m, hten the image that forms at a point will be
real and inverted
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The equation v=aΔt is sometimes used to find velocity when acceleration and time are known. Another form of this equation is v= Vo+aΔt. In this second form of the equation, the function of the term Vo is to
allow the equation to be used even when an object has a nonzero initial velocity.
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A rectangular box 10x10x5 cm is made of a material that has a density 25% that of water. If it is placed in a container of water, how many cubic centimeters of the rectangular solid will be below the surface of the water?
125 cm3
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In the early twentieth century, Robert Millikan created electrically charged oil droplets and then determined their electrical charge by calculating the magnitude of the electrical charge that would suspend them in midair in opposition to gravity. He found that the electrical charge on each oil droplet was always an integar multiple of what we now know as the basic unit charge. Millikan's experiment is credited with discovering
the charge of a single electron.
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