Why is it that the most ancient rocks are found on the continents, and not on the ocean floor?
What will be an ideal response?
Answer: The ocean floors are sites of crustal formation. New crust generated at a spreading center, pushes older crust away. In general, continental crust does not get subducted because of its low density. Older oceanic crust has been subducted, while older continental crust has not.
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Dwarf planets grew large in the solar nebula but never became large enough to capture or eject other objects orbiting nearby
a. True b. False Indicate whether the statement is true or false
The slow ________ of Mercury was first determined using radar signals sent from Earth
Fill in the blank(s) with correct word
A changing current in one loop of wire can induce a current in another loop of wire even though the wires do not touch. The induced current appears almost instantaneously for loops close together. How can this energy exchange happen?
a. This is one of those things for which science has no adequate explanation yet. b. The second loop is affected by the thermal exchange from the heating of the first loop. c. It is a gravitational effect on the electrons. d. It is done via an electromagnetic wave.
A neutral hollow spherical conducting shell of inner radius 1.00 cm and outer radius 3.00 cm has a +2.00-µC point charge placed at its center. Find the surface charge density
(a) on the inner surface of the shell. (b) on the outer surface of the shell.