FiltersDone

Question type

Essay

Multiple Choice

Short Answer

True False

Matching

Exam 4: Atomic Physics and Spectra

Show Answer

Share

---

All types

Filters

Study FlashcardsPractice ExamLearn

Question 51

Multiple Choice

Review LaterAdd Note

Review Later

Which of these statements is true if the star Betelgeuse has a lower surface temperature than the Sun? (Assume that IR means infrared radiation and UV means ultraviolet radiation.)

A) Betelgeuse emits more IR and less UV flux than the Sun.
B) Betelgeuse emits more IR and more UV flux than the Sun.
C) Betelgeuse emits less IR and more UV flux than the Sun.
D) Betelgeuse emits less IR and less UV flux than the Sun.

Correct Answer

verified

Show Answer

Question 52

Multiple Choice

Review LaterAdd Note

Review Later

An object is observed to show no Doppler shift. As a result, only one of these statements cannot describe the motion of the object. Which one?

A) The object is stationary.
B) The object has only a transverse motion.
C) The object has only a proper motion.
D) The object has only a radial motion.

Correct Answer

verified

Show Answer

Question 53

Multiple Choice

Review LaterAdd Note

The minimum temperature reached on the surface of Mars, -140°C, is represented on the absolute (Kelvin) temperature scale as

According to the Doppler effect,

If curves of intensity versus wavelength are plotted for a single object at various temperatures, it is found that the curves never cross. Why is this important?

Which of these are isotopes of carbon?

The series of spectral absorption lines in the infrared part of the spectrum, known as the Paschen series, results from atomic transitions in hydrogen atoms in which electrons are lifted from which energy level to all higher atomic energy levels?

The atomic number of the isotope ²³⁸U of uranium is 92. The nucleus of this isotope contains

When electrons jump from higher levels in hydrogen atoms to the level n = 2, the resulting spectrum will consist of a

An atom consists of

Two physicists, one on the east coast and one on the west coast of North America, discover that they have constructed ideal blackbodies in their laboratories. The two blackbodies are made from very different materials. Without conducting tests, they know that the radiation emitted by these two objects will be

If a certain gas is heated and observed through a grating, a bright line spectrum will be seen. If instead a source of continuous spectrum shines through a cooler sample of this same gas, a dark absorption spectrum is observed. How do the positions of the lines in these two spectra compare?

Two objects are moving directly away from an observer at the same speed. One object, however, is twice as far away as the other. How do their Doppler shifts compare?

Cepheid variable stars pulsate regularly in size. During the contraction part of the cycle, when the star's temperature is increasing, the peak wavelength of the emitted radiation will

Iron has 26 protons, and one isotope of iron, ⁵⁷Fe, has an atomic mass of about 57. How many neutrons are in the nucleus of this atom?

The peak wavelength emitted in the spectrum of a blackbody is proportional to what power of the blackbody's Kelvin temperature?

The hot, dense gas existing on the Sun emits energy

A particular spectrograph, used by an astronomer to disperse light into its colors, contains a piece of glass that has been ruled with thousands of closely spaced, parallel lines. What is the name of this piece of glass?

An astronomer plots the intensity of the radiation emitted from an opaque, perfectly absorbing object at a certain temperature versus its wavelength. As the temperature increases, the wavelength at which the spectrum peaks becomes shorter and shorter. This is an example of

In what units does one measure flux F?