Exam 5: The Nature of Light

An atom of hydrogen undergoes a collision with another atom in a hot gas, the energy of collision being about 11 eV. What is the probable outcome of this collision in terms of the atom?

How is a star's spectrum changed when looking at the absorption spectrum from a star moving away from you as compared to if the star were stationary?

What is one fundamental difference between x rays and radio waves?

During a dust storm the Sun often appears to redden. This means that the particles of dust:

Rømer calculated the speed of light by observing the large moons of Jupiter being eclipsed by Jupiter while that planet was at opposition and while it was at superior conjunction. How large is the difference in the Jupiter-Earth distance when Jupiter is at opposition and when it is at superior conjunction?

Who was the first person to suggest that light is made of particles?

The total energy flux F of radiation emitted per unit area by a blackbody (e.g., star) is related to its temperature T and a constant σ by which equation?

How many neutrons are there in the nucleus of the isotope ¹⁸O of oxygen?

Can a cooler object ever emit more radiation than a warmer object?

White light passes through a prism and separates into a spectrum of colors. A second prism is placed so that only the green light from the first prism falls upon it. After passing through this second prism the light will be:

The radius of the Sun is about 1/200 of an astronomical unit. What happens to the flux of solar energy as it travels from the Sun's surface to Earth?

What is the wavelength of the radiation whose photons have 1 eV of energy?

Compare two electron transitions in hydrogen: n = 3 → n = 1 and n = 2 → n = 1. Which produces the photon with the higher frequency?

The first experiment in which the speed of light was measured precisely involved:

When a hydrogen atom is excited, it emits visible radiation. This radiation is predominantly in the:

Assuming that Uranus was at opposition to Earth when Voyager II sent back its historic (and magnificent) pictures from Uranus in January 1986, how long did those signals take to arrive after transmission by Voyager? The average distance of Neptune from the Sun is about $2871 \times 10^{6} \mathrm{~km}$ .

Balmer constructed his formula for the hydrogen spectral lines by trial and error manipulations of large amounts of experimental measurement data. This is somewhat like the procedure followed by:

In order of increasing frequency, some of the colors that the visible spectrum contains are:

Proxima Centauri, our Sun's nearest stellar neighbor, has a surface temperature of about 3300 K. At what wavelength does Proxima Centauri emit its most intense radiation?

Two physicists, one in Australia, the other in the United States, find that each has constructed an ideal blackbody in the laboratory. The two blackbodies are made from very different materials. Without conducting tests, they know that the radiation emitted by these two objects will be: