What is the major observational difference between a Seyfert galaxy and a normal spiral galaxy?
a. Normal spiral galaxies usually have shorter spiral arms.
b. Normal spiral galaxies never contain a supermassive black hole at their center.
c. The central region of a Seyfert galaxy is much brighter.
d. Seyfert galaxies don't contain any star formation.
C
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First Law of Thermodynamics: A monatomic ideal gas undergoes an isothermal expansion at 300 K, as the volume increased from 0.050 m3 to 0.150 m3. The final pressure is 130 kPa. How much heat is transferred to the gas during this expansion? (R = 8.31 J/mol ? K)
A. 21 kJ B. 11 kJ C. -21 kJ D. -11 kJ E. 0 kJ
A baseball is thrown and lands 120 m away. While the ball is in flight, assuming the effect of air friction is negligible, which of the following is true?
a. At maximum height the ball has its greatest kinetic energy. b. The horizontal component of the baseball's kinetic energy is constant. c. The vertical component of the baseball's kinetic energy is constant. d. The mechanical energy of the baseball is greater when nearer to the ground. e. No answer above is correct.
The velocity of a transverse wave on a stretched string or cord depends only on the tension in the cord
Indicate whether the statement is true or false
Every spinning electron is
A) electrically charged. B) a tiny magnet. C) both of these D) none of the above