Exam 5: Light: the Cosmic Messenger

The following questions refer to the diagram below. The levels represent energy levels in a hydrogen atom. Each level is labeled with its energy (above the ground state of Level 1) in units of electron/volts (eV). The labeled transitions represent an electron moving between energy levels. -Which transition, as shown, is not possible?

Which of the following properties cannot be determined from a spectrum of a star?

Without telescopes or other aid, we can look up and see the Moon in the night sky because it

Suppose you look at a spectrum of visible light by looking through a prism or diffraction grating. How can you decide whether it is an emission line spectrum or an absorption line spectrum?

Cell phone signals passing through walls is an example of

Draw and label a simple diagram of the following: a. a refracting telescope b. a reflecting telescope

A radio telescope and an optical telescope of the same size have the same angular resolution.

An electron-volt is

In what wavelength range was interferometry first routinely used?

What is an artificial star?

State the two laws of thermal radiation.

What is the purpose of adaptive optics?

Which of the following best describes the fundamental difference between two different chemical elements (such as oxygen and carbon)?

Imagine a planet like Earth orbiting the Sun, but in an orbit with an average distance of 2 AU. What is its orbital period?

Suppose that Star X and Star Y both have redshifts, but Star X has a larger redshift than Star Y. What can you conclude?

Everything looks red through a red filter because

Which of the following is always true about images captured with X-ray telescopes?

The spectra of most galaxies show redshifts. This means that their spectral lines ________.

The following questions refer to the diagram below. The levels represent energy levels in a hydrogen atom. Each level is labeled with its energy (above the ground state of Level 1) in units of electron/volts (eV). The labeled transitions represent an electron moving between energy levels. -Which transition represents the electron that emits a photon with the highest energy?

What is the purpose of interferometry?