Which of the following objects do you expect to find at the center of a planetary nebula?
A. neutron star
B. planet
C. black hole
D. white dwarf
Answer: D
You might also like to view...
Semiconductors: The energy gap between the valence and conduction bands in a certain semiconductor is 1.25 eV. What is the threshold wavelength for optical absorption in this substance? (c = 3.00 × 108 m/s, h = 6.626 × 10-34 J ? s)
A. 599 nm B. 959 nm C. 873 nm D. 994 nm
An earthquake emits both S waves and P waves which travel at different speeds through the Earth. A P wave travels at 9 000 m/s and an S wave travels at 5000 m/s. If P waves are received at a seismic station 1.00 minute before an S wave arrives, how far away is the earthquake center?
A. 88.9 km B. 1200 km C. 675 km D. 240 km E. 480 km
An alternate equation for power in an electric circuit is P = IR
a. True b. False Indicate whether the statement is true or false
The planetary model of the atom is a more detailed, or sophisticated, model than the simpler Greek model of the atom. The planetary model is useful because, unlike the Greek model, it can explain
A) the differences between the three states of matter. B) electrical phenomena such as electric current. C) the microscopic meaning of thermal energy. D) certain subtle "quantum" effects. E) gas pressure, including air pressure.