1. If you are standing at Earth’s equator at noon, which of the following will be directly overhead?

   	a.	The polar star.
   	b.	The South Pole.
   	c.	The Sun.
   	d.	The north celestial pole.
   	e.	None of the above.

5 points

QUESTION 2

1. The difference between the Moon's sidereal and synodic period is attributed to:

   	a.	Earth’s rotations around its axis and the Moon's revolution around Earth.
   	b.	Earth’s revolution around the Sun and the Moon's revolution around Earth.
   	c.	the Moon's revolution around Earth.
   	d.	the Moon's tidal effects on Earth.
   	e.	None of the above.

5 points

QUESTION 3

1. Why do the Sun, the Moon and stars appear to move from east to west across the sky?

   	a.	The apparent motion of the Sun, the Moon and stars is caused by Earth's rotation around its axis from east to west.
   	b.	The apparent motion of the Sun, the Moon, and stars is caused by Earth's rotation around its axis from west to east.
   	c.	The Sun, the Moon and stars always move from east to west.
   	d.	None of the above.

5 points

QUESTION 4

1. If you are standing at the Earth’s equator, which of the following will be directly overhead?

   	a.	The polar star.
   	b.	The celestial equator.
   	c.	The South Pole.
   	d.	The north celestial pole.
   	e.	None of the above.

5 points

QUESTION 5

1. A solar eclipse typically lasts less than 7 minutes because:

   	a.	of Earth's rotation rate of approximately 24 hours per day.
   	b.	of Earth orbits the Sun at the orbital speed of 29 km/s.
   	c.	the Moon’s shadow moves across Earth’s surface at speeds greater than 0.5 km per second.
   	d.	All of the above.

5 points

QUESTION 6

1. The New Moon is observed when:

   	a.	the Moon is positioned between Earth and the Sun.
   	b.	Earth is positioned between the Moon and the Sun.
   	c.	the Sun is positioned between Earth and the Moon.
   	d.	all planets aligned with Earth and Sun.

5 points

QUESTION 7

1. Why do stars observed at the North Pole never rise or set?

   	a.	Because of the Sun's revolution around Earth, all stars visible at the North Pole revolve around Polaris that appears directly overhead.
   	b.	Because of Earth's rotation about its axis, all stars visible at the North Pole revolve around Polaris that appears directly overhead.
   	c.	Some of them do, but we never observe them.
   	d.	None of the above.

5 points

QUESTION 8

1. The plane of the ecliptic is tilted with respect to the celestial equator at 23.5 degrees. This reflects the fact that:

   	a.	the Sun moves from east to west as it orbits Earth.
   	b.	the Sun moves from east to west as Earth orbits the Sun.
   	c.	Earth's axis is tilted by the same angle with respect to the orbital plane.
   	d.	None of the above.

5 points

QUESTION 9

1. Which of the following is the correct order?

   	a.	Protons, quarks, atom, molecule.
   	b.	Atom, molecule, quark, proton.
   	c.	Quark, proton, atom, molecule.
   	d.	None of the above.

5 points

QUESTION 10

1. About how much larger is the Sun in size than Earth?

   	a.	10.
   	b.	100.
   	c.	10000.
   	d.	1000000.
   	e.	None of the above.

5 points

QUESTION 11

1. How is a light year defined?

   	a.	As the distance sound waves travel in a year.
   	b.	As an average distance between Earth and the Sun.
   	c.	As the distance light travels in a year.
   	d.	It is not a measure of distance, but time (in years).

5 points

QUESTION 12

1. The Full Moon is observed when:

   	a.	the Moon is positioned between Earth and the Sun.
   	b.	Earth is positioned between the Moon and the Sun.
   	c.	the Sun is positioned between Earth and the Moon.
   	d.	all planets are aligned with Earth and the Sun.

5 points

QUESTION 13

1. 1 AU is:

   	a.	A distance light travels in a year.
   	b.	A unit of mass of an average black hole.
   	c.	An average distance between Earth and the Sun.
   	d.	An average distance between the Sun and the closest star.

5 points

QUESTION 14

1. In 12,000 years, Earth's axis will point toward Vega instead of Polaris because:

   	a.	Vega moves extremely fast in the direction of Polaris, while Polaris moves in the opposite direction.
   	b.	Earth moves extremely fast in the direction of Polaris, while Polaris moves in the opposite direction.
   	c.	of precession of Earth's axis with the period of 26,000 years.
   	d.	the Moon's tidal effects on Earth.

5 points

QUESTION 15

1. Seasons on Earth are caused:

   	a.	by Earth's revolution around the Sun.
   	b.	by the Sun's revolution around Earth.
   	c.	by Earth's rotation about its axis.
   	d.	due to a combination of the revolution of Earth's rotation around the Sun and its axis tilt with respect to ecliptic.
   	e.	None of the above.

5 points

QUESTION 16

1. Which of the following systems are bound together by gravity?

   	a.	The galaxy.
   	b.	The Sun.
   	c.	Earth.
   	d.	The local group of galaxies.
   	e.	All of the above.
   	f.	None of the above.

5 points

QUESTION 17

1. A total solar eclipse takes place only during:

   	a.	the vernal equinox.
   	b.	a Full Moon, when Earth is directly between the Sun and the Moon.
   	c.	a New Moon, when the Moon is directly between the Sun and Earth and faces us with its “unlit” side.
   	d.	the Moon's first quarter.
   	e.	All of the above.

5 points

QUESTION 18

1. If you are standing at Earth’s North Pole, which of the following will be directly overhead?

   	a.	The Polar star.
   	b.	The celestial equator.
   	c.	The Sun.
   	d.	The south celestial pole.
   	e.	None of the above.

5 points

QUESTION 19

1. The major difference between the duration of the sidereal and synodic month is caused by:

   	a.	the gravitational pull from the galaxy's center.
   	b.	the Sun's motion around the center of the galaxy.
   	c.	our inaccuracies in measuring the position of the Sun with respect to the fixed stars.
   	d.	the effect of the change in direction of Earth’s axis, or precession.
   	e.	the combined motion of Earth’s around the Sun and the Moon's revolution around Earth.

5 points

QUESTION 20

1. Which of the following is the correct order?

   	a.	The Milky Way galaxy, the local group, supercluster, the Sun.
   	b.	The solar system, The Milky Way galaxy, the local group, clusters of galaxies.
   	c.	Star, planet, cluster of galaxies, galaxy.
   	d.	Planet, star, galaxy, local group, galaxy cluster.
   	e.	None of the above.

1. The Copernicus's heliocentric model of the universe replaced Ptolemy's geocentric model because:

   	a.	it was simpler and more elegant in explaining orbital speeds of planets.
   	b.	it provided a simple explanation of retrograde motion, and variation in brightness of planets and phases of Venus.
   	c.	it provided a simple explanation of variation in brightness of planets.
   	d.	All of the above.

5 points

QUESTION 2

1. Newton's Third Law is observed when:

   	a.	a body moves along a straight trajectory with constant speed.
   	b.	an astronaut experiences a free-fall.
   	c.	two bodies interact with each other.
   	d.	All of the above.
   	e.	None of the above.

5 points

QUESTION 3

1. To "break free" from Earth's gravitational field, a body needs:

   	a.	to acquire the escape velocity.
   	b.	to circle around the planet.
   	c.	to spin faster.
   	d.	to acquire at least 11.2 km/s.
   	e.	Both A and D.

5 points

QUESTION 4

1. Kepler's Third law states:

   	a.	that the square of a planet’s orbital period is proportional to the cube of its distance to a central star.
   	b.	that as a planet gets close to its central star, it moves faster.
   	c.	that a planetary path is an ellipse with the Sun at one of its foci.
   	d.	the spin rate of a planet and its mass.
   	e.	None of the above.

5 points

QUESTION 5

1. The Law of Universal Gravitation can be applied to:

   	a.	planetary motions around their central star.
   	b.	stellar motions around the center of our galaxy.
   	c.	motion of the Milky Way galaxy in a cluster of galaxies.
   	d.	motions of spacecraft around Earth.
   	e.	motion of the Moon around Earth.
   	f.	All of the above.

5 points

QUESTION 6

1. When Earth, the Moon, and Sun are aligned with respect to each other, then we should always observe:

   	a.	the lowest tides called Neap Tides.
   	b.	the highest tides called Spring Tides.
   	c.	a solar eclipse.
   	d.	a lunar eclipse.
   	e.	All of the above.

5 points

QUESTION 7

1. Gravitational potential energy of a planet orbiting its central star is:

   	a.	always positive.
   	b.	always zero.
   	c.	always negative.
   	d.	varies between being positive and negative.
   	e.	All of the above.

5 points

QUESTION 8

1. Retrograde motions of planets as observed from Earth can be explained:

   	a.	if a planet that is closer to the Sun moves faster than those farther away from it.
   	b.	if a planet that is closer to the Sun moves slower than those farther away from it.
   	c.	when a planet’s orbital velocity is exactly equal to Earth’s velocity on its orbit.
   	d.	because all planets move in the opposite direction with respect to Earth’s motion.
   	e.	None of the above.

5 points

QUESTION 9

1. Kepler's Second law states:

   	a.	that the square of a planet’s orbital period is proportional to the cube of its distance to a central star.
   	b.	that as a planet gets closer to its central star, it moves faster.
   	c.	that a planetary path is an ellipse with the Sun at one of its foci.
   	d.	the spin rate of a planet and its mass.
   	e.	None of the above.

5 points

QUESTION 10

1. Newton's First Law specifies that:

   	a.	a body will move with constant acceleration along a straight line if there is no net force applied to it.
   	b.	a body will move with increased acceleration along a curved line if there is no net force applied to it.
   	c.	a body will move with zero acceleration along a curved line if there is no net force applied to it.
   	d.	a body will move with constant speed along a straight line if there is no net force applied to it.
   	e.	None of the above.

5 points

QUESTION 11

1. As distance between two stars reduces by half, the force of gravity exerted on them:

   	a.	becomes 9 times greater.
   	b.	becomes 16 times weaker.
   	c.	becomes 4 times greater.
   	d.	becomes 4 times weaker.
   	e.	All of the above.

5 points

QUESTION 12

1. An astronaut on the International Space Station (ISS) experiences weightlessness because:

   	a.	of zero gravity exerted to his or her body.
   	b.	of zero mass in space.
   	c.	of zero acceleration in space.
   	d.	the astronaut and the ISS both experience free fall due to Earth's gravity force.
   	e.	None of the above.

5 points

QUESTION 13

1. The Moon spirals away from us at a rate of about 2 inches per year because of:

   	a.	the Sun's gravity exerted to it.
   	b.	the momentum acquired from another body during its formation.
   	c.	the gravitational tidal force exerted by Earth to the Moon.
   	d.	All of the above.
   	e.	None of the above.

5 points

QUESTION 14

1. The scientific method requires that a researcher will:

   	a.	collect and analyze data to find a pattern.
   	b.	formulate a hypothesis and make predictions.
   	c.	test predictions.
   	d.	refine or discard of an original hypothesis based on new data.
   	e.	Only A and B.
   	f.	Only B and C.
   	g.	All of the above.
   	h.	None of the above.

5 points

QUESTION 15

1. The law of conservation of energy suggests that the total amount of energy in the universe:

   	a.	can either decrease or increase.
   	b.	can only increase with time.
   	c.	can only decrease with time.
   	d.	cannot change in time.
   	e.	None of the above.

5 points

QUESTION 16

1. A body's weight on a planet depends:

   	a.	on the planets radius only.
   	b.	on the planet's mass only.
   	c.	on the planet’s gravitational acceleration.
   	d.	All of the above.
   	e.	None of the above.

5 points

QUESTION 17

1. If observations show that a celestial body moves along a curved line (or a circle), then we conclude that:

   	a.	its motion is affected by an external force.
   	b.	its motion is affected by another massive body exerting gravity force on it.
   	c.	it experiences a centripetal acceleration.
   	d.	its velocity changes along the planet's trajectory.
   	e.	A and B.
   	f.	All of the above.
   	g.	None of the above.

   1. Light can be described as:

      	a.	an electromagnetic wave.
      	b.	a sound wave.
      	c.	an oscillation of electric and magnetic fields in two mutually perpendicular planes to the direction of light propagation.
      	d.	Both A and C.
      	e.	None of the above.

   5 points

   QUESTION 2

   1. What type of waves exhibit the Doppler effect?

      	a.	Sound waves.
      	b.	Gamma-rays.
      	c.	X-rays.
      	d.	Water waves.
      	e.	All of the above.

   5 points

   QUESTION 3

   1. Refraction of light waves occurs:

      	a.	when light spreads into a rainbow of colors.
      	b.	when a wave changes direction of propagation as it passes from one medium to another at any angle other than 90° or 0°.
      	c.	when it gets reflected from the surface.
      	d.	None of the above.

   5 points

   QUESTION 4

   1. Refractors have disadvantages over reflectors because:

      	a.	their primary objective (lens) suffers from chromatic aberration.
      	b.	their primary objective (lens) is under their own weight.
      	c.	of their greater manufacturing cost.
      	d.	two sides of the refractor telescope's objective need to be perfect rather than one side in reflectors.
      	e.	All of the above.

   5 points

   QUESTION 5

   1. X-ray telescopes cannot be used for observations from Earth’s surface because:

      	a.	x-ray images will be too blurry to construct a quality image.
      	b.	x-ray emission is blocked by Earth’s atmosphere.
      	c.	x-ray emission from astronomical objects is very weak and extremely large x-ray telescopes are needed.
      	d.	All of the above.

   5 points

   QUESTION 6

   1. An amateur telescope with the focal length of an objective, F=1000 mm and the focal length of an eyepiece, f=10 mm, will produce magnification of:

      	a.	1000 times.
      	b.	10 times.
      	c.	100 times.
      	d.	100000 times.
      	e.	0.1 times.

   5 points

   QUESTION 7

   1. The resolving power of a telescope with a larger mirror is:

      	a.	smaller.
      	b.	greater.
      	c.	the same.
      	d.	dependent of the focal length.
      	e.	independent of its diameter.

   5 points

   QUESTION 8

   1. As a body gets hotter, it emits most of its power:

      	a.	at shorter wavelength.
      	b.	at longer wavelength.
      	c.	radio band.
      	d.	at higher frequency.
      	e.	Both A and D.
      	f.	None of the above.

   5 points

   QUESTION 9

   1. A telescope's resolving power measures its ability to view:

      	a.	fainter objects.
      	b.	more distant objects.
      	c.	finer structures.
      	d.	higher frequency objects.
      	e.	younger objects.

   5 points

   QUESTION 10

   1. As light from a star passes through a rarefied cold gas and then passes through a prism, it produces:

      	a.	a continuous spectrum.
      	b.	an emission line spectrum.
      	c.	an absorption line spectrum.
      	d.	All of the above.
      	e.	None of the above.

   5 points

   QUESTION 11

   1. Photon’s energy is directly proportional to its:

      	a.	amplitude.
      	b.	frequency.
      	c.	wavelength.
      	d.	mass.
      	e.	All of the above.
      	f.	None of the above.

   5 points

   QUESTION 12

   1. As light from an opaque object (star) passes through a prism, it produces:

      	a.	a continuous spectrum.
      	b.	an emission line spectrum.
      	c.	an absorption line spectrum.
      	d.	All of the above.
      	e.	None of the above.

   5 points

   QUESTION 13

   1. As a star moves toward an observer, the wavelength of the observed absorption lines:

      	a.	becomes longer (or red-shifted).
      	b.	becomes shorter (or blue-shifted).
      	c.	does not change.
      	d.	All of the above.
      	e.	None of the above.

   5 points

   QUESTION 14

   1. As a light source moves away from an observer, the wavelength of the observed emission lines:

      	a.	becomes longer (or red-shifted).
      	b.	becomes shorter (or blue-shifted).
      	c.	does not change.
      	d.	All of the above.
      	e.	None of the above.

   5 points

   QUESTION 15

   1. The frequency of a light source at 100 MGh (megahertz) corresponds to the wavelength of:

      	a.	1 m.
      	b.	100 nm.
      	c.	3 microns.
      	d.	3 m.
      	e.	1 km.

   5 points

   QUESTION 16

   1. The highest energy photons belong to the following spectral band:

      	a.	x-ray.
      	b.	gamma-ray.
      	c.	visible.
      	d.	IR band.
      	e.	radio.

   5 points

   QUESTION 17

   1. Which of the spectral bands has the longest wavelengths?

      	a.	X-ray.
      	b.	Gamma-ray.
      	c.	Visible.
      	d.	IR band.
      	e.	Radio.

   5 points

   QUESTION 18

   1. To construct an image gamma-ray telescopes use:

      	a.	wave properties of light.
      	b.	particle properties of light.
      	c.	light refraction.
      	d.	light dispersion.
      	e.	All of the above.

   5 points

   QUESTION 19

   1. An atom will be excited from its ground state to a higher energy state if:

      	a.	it emits a photon with the fixed energy corresponding to the energy difference between states.
      	b.	it absorbs a photon with the fixed energy corresponding to the energy difference between states.
      	c.	it absorbs a photon with any energy.
      	d.	it gets decayed.
      	e.	None of the above.

   5 points

   QUESTION 20

   1. Adaptive optics can increase the angular resolution of an image by:

      	a.	burning Earth’s atmospheric path by a laser.
      	b.	observing in the x-ray band.
      	c.	taking a telescope out of Earth’s atmosphere.
      	d.	correcting for the effects of atmospheric turbulence in real time.