Astro Practice 1

Kepler found the orbits of planets are ellipses, not circles.

• True

• False

The most accurate Greek attempt to explain planetary motion was the model of:

• Aristotle

• Pythagoras

• Hipparchus

• Ptolemy

• Eratosthenes

Scientists today do not accept the Ptolemaic model because:

• it is ancient history.

• it was too complicated, compared to Copernicus' heliocentric model.

• it has been shown that Ptolemy faked his data.

• it had no explanation for retrograde motion.

• the work of Tycho and Kepler showed the heliocentric model was more accurate.

Which of the following is a contribution to astronomy made by Galileo?

• The astronomical telescope can show us far more detail than the eye can.

• Jupiter has four moons orbiting it.

• The Moon has craters, mountain, valleys, and dark flat areas on its surface.

• Venus appears almost fully lit when it lies on the far side of the Sun.

• all of the above

Which of these is constant for ALL types of electromagnetic radiation in a vacuum?

• amplitude

• wavelength

• frequency

• velocity

• photon energy

Of all the forms of electromagnetic radiation, the one with the lowest frequency is

• gamma rays

• ultraviolet rays

• visible light

• microwaves

• radio waves

With electromagnetic radiation, when the energy of a higher frequency wave is ________ the energy of a lower frequency wave

• Less than

• Greater than

• Equal to

• not comparable to

Colors appear different to us because of their photons' different:

• speeds

• amplitudes

• frequencies

• magnetic fields

• polarization

There are no X-ray telescopes on Earth because

• they are too expensive to build

• no one has yet invented an X-ray telescope that works

• we can't figure out how to direct an X-ray beam through space

• X-rays don't penetrate Earth's atmosphere

• there are no astronomical objects that emit X-rays

The radiation our eyes are most sensitive to lies in the color

• red at 656.3 nm

• yellow-green at about 550 nm

• violet at 700 nm

• blue at 432.1 nm

• black at 227 nm