What evidence suggests that Mercury contracted within about a billion years after it formed?
Fill in the blank(s) with the appropriate word(s).
Answer: The surface of Mercury is marked by long, high cliffs. Such features result from tectonic compression, but there are no corresponding features due to tectonic stretching. This suggests the whole planet contracted as it rapidly cooled in its early history. We can date the contraction from the age of the volcanic flows on its surface: volcanic (and all geologic) activity probably came to an abrupt halt as a result of the planet's contraction.
You might also like to view...
A key difference between the tragedy of the commons and TANSTAAFL is that
a. TANSTAAFL applies to chemistry, the tragedy of the commons to physics. b. both apply to all situations; so there is no difference. c. TANSTAAFL applies to sociology, the tragedy of the commons to economics. d. TANSTAAFL applies to economics, the tragedy of the commons to physical systems. e. TANSTAAFL applies to physical systems, the tragedy of the commons to socialsystems.
An air sample is contaminated with 15O, which has a half-life of 2.03 min. One possible way to minimize its hazard is to pass it through a long pipe to allow it to decay inside the pipe until it can be safely released into the atmosphere
If the oxygen moves at a speed of 1.1 m/s in the pipe, how long must the pipe be for the sample to have decayed to 3.0% of its original activity just as it leaves the pipe? A) 680 m B) 8.0 m C) 7.0 m D) 2.0 m
Light of wavelength 400 nm falls on a metal surface having a work function 1.70 eV
What is the maximum kinetic energy of the photoelectrons emitted from the metal? (c = 3.00 × 108 m/s, h = 6.626 × 10-34 J ? s = 4.141 × 10-15 ev ? s, 1 eV = 1.60 × 10-19 J) A) 1.41 eV B) 1.70 eV C) 3.11 eV D) 2.82 eV E) 4.52 eV
The boundary shown is that of a uniform magnetic field directed in the positive z direction. An electron enters the magnetic field with a velocity pointing along the x axis and exits 0.63 ?s later at point A. What is the magnitude of the magnetic field?
a.
18 ?T
b.
14 ?T
c.
28 ?T
d.
34 ?T
e.
227 ?T