Simon P. Balm

Astronomy 1/2

Test #1 Sample Questions




1. In following the principles of the scientific method, a theory proposed to explain a given phenomenon must

A. explain all previous and reliable observations in a consistent manner but need not suggest new tests for the theory since a theory should be complete in itself.

B. explain all known and reliable observations and predict new experiments and observations.

C. agree with and build on previous theories but need not explain all observations since some of these may be erroneous.

D. predict new and different experiments that will extend the scope of the theoretical understanding but need not explain all the previous observations since no theory is expected to explain everything completely.


2. One arc second is equal to

A. 1/3600 degree.

B. 1/60 of an arc minute.

C. 1/60 of a full circle.

D. 1/3600 of a full circle.


3. The average distance from the Earth to the Sun, 149,600,000 km can be written in shorthand notation as

A. 1.496 109 km.

B. 1.496 106 km.

C. 1.496 108 km.

D. 1.496 107 km.


4. If a star is seen to explode in our sky in 2005 and it is 5 light years away, when did the star actually explode?

A. 2005

B. 2010

C. 1995

D. 2000


5. Which of the following statements correctly describes the relationship between stars and constellations?

A. Only those stars that were visible to the ancient Greeks are located in constellations.

B. Only the brighter stars are in constellations.

C. Only stars within the zodiac close to the ecliptic, the Earth's orbital plane, are located in constellations.

D. Every star is located in a constellation.


6. The most easily observed motion in the night sky is caused by the

A. revolution of the Earth around the Sun.

B. motion of stars with respect to each other in the sky.

C. motion of the planets along their orbits around the Sun.

D. rotation of the Earth on its axis.


7. In what direction will the Sun rise on Nov 1st as seen from Santa Monica?

A. due E





8. The declination of a star in our sky is defined as the angle between the

A. Earth's equator and the star.

B. celestial equator and the star.

C. Greenwich Meridian and the star.

D. vernal equinox and the star.


9. What phase of the moon occurs before waxing crescent?

A. new moon

B. 1st quarter

C. 3rd quarter

D. full


10. If we see more than half of the illuminated hemisphere of the moon but less than all of it and the moon is trailing the sun in the sky, what is the phase?

A. waning crescent

B. waxing crescent

C. waning gibbous

D. waxing gibbous


11. The Sun rises due east in the sky when viewed from any site

A. on Earth only on the first day of spring and the first day of fall.

B. on the equator on every day of the year.

C. along the Earth's equator at midsummer and midwinter.

D. on Earth on the first day of summer and the first day of winter.


12. During a solar eclipse, the

A. Sun comes between the Earth and the Moon.

B. Moon comes between the Earth and the Sun.

C. Sun goes below the horizon.

D. Earth comes between the Sun and the Moon.


13. Which of the following statements correctly describes why Copernicus decided that the orbits of Mercury and Venus were smaller than the orbit of Earth?

A. Both planets show a complete cycle of phases, like the Moon.

B. Both planets can sometimes be seen high in our sky at midnight.

C. Both planets are very bright in the sky as seen from Earth.

D. Both planets stay fairly close to the Sun in our sky.


14. Which of the following statements correctly states the significance of Galileo's observation that Jupiter has satellites (moons)?

A. It was interesting but had no particular significance.

B. It showed that bodies can orbit an object other than Earth.

C. It showed that Jupiter must be four times the size of Earth (since Jupiter has four moons and Earth has one).

D. It showed that Jupiter must orbit around the Sun, not around Earth.


15. If the line joining a planet to the Sun sweeps out a particular area in one day, then in 2 days it will sweep out

A. half the area.

B. exactly twice the area.

C. more than twice the area if the planet is approaching perihelion and less than twice the area if it is leaving perihelion.

D. less than twice the area if the planet is approaching perihelion and more than twice the area if it is leaving perihelion.


16. What is the mathematical relationship between t and d in the equation: t = d/v ?,

A. inverse

B. inverse square

C. indirect

D. direct


17. Which Law of Kepler relates the distance of a planet from the Sun and how long it takes to orbit?

A. 1st

B. all three

C. 2nd

D 3rd


18. In the heliocentric theory, what lies at the center of the Universe?

A. Jupiter

B. the Moon

C. the Sun

D. the Earth


19. Earth exerts a force on you as you stand on its surface. What is the size of the force exerted on Earth by you, when compared to the above force?

A. zero, you do not exert a force on Earth

B. the same

C. very small, because your mass is small compared to that of Earth

D. twice as large, because of Earth's rotation


20. Newton's 2nd Law states that if a force were applied to an object in space, the resultant acceleration would depend on the

A. initial speed of the object.

B. mass of the object.

C. initial position of the object.

D. size of the object.


21. During one complete year, an observer at the South Pole would be able to see what fraction of the overall sky?

A. 50%

B. 25%

C. 100%

D. 75%


22. The strength of gravity on Mars is about 40% of that on Earth. If you were to visit Mars, what would happen to your mass and weight compared to when you were on Earth?

A. Your weight would be the same but your mass would be less.

B. Your weight and mass would both be unchanged from when you were on Earth.

C. Your mass would be the same but your weight would be less.

D. Your weight and mass would both be less than when you were on Earth.


23. In the years after Newton published his laws of motion, it was found that the observed positions of the planet Uranus did not match the predictions of Newton's theory. The reason for this turned out to be the

A. perturbing effect of Pluto, which at that time had not yet been discovered.

B. perturbing effects of Jupiter and Saturn, whose masses at that time were not accurately known.

C. perturbing effect of Neptune, which at that time had not yet been discovered.

D. weakening of gravity with increasing distance from the Sun.


24. In a radio wave transmitter (such as that used by a radio or TV station), when the frequency of the signals is increased, the

A. wavelength is decreased.

B. speed of transmission of the waves is increased.

C. wavelength and speed of transmission both increase.

D. wavelength remains constant.


25. When electromagnetic radiation (e.g. light) is Doppler-shifted by motion of the source away from the detector the

A. frequency remains the same, but the wavelength is shortened, compared to the emitted radiation.

B. detected wavelength is longer than the emitted wavelength.

C. speed of the radiation is reduced below the emitted speed.

D. measured frequency is higher than the emitted frequency.


26. Choose the correct sequence of electromagnetic radiations, in order of increasing wavelengths.

A. radio, IR, visible, UV

B. UV, visible, radio, IR

C. UV, visible, IR, radio

D. visible, UV, IR, radio


27. Radio waves travel through space at what speed?

A. much faster than the speed of light

B. faster than the speed of light, since their wavelength is longer

C. slower than the speed of light

D. at the speed of light, 3 108 m/s


28. Which of the following properties is/are the same for both the isotopes 15N of nitrogen and 15O of oxygen?

A. only the atomic mass

B. the mass and the number of neutrons

C. only the number of protons

D. only the number of neutrons


29. What is chromatic aberration in a telescope?

A. Light striking the lens at different distances from the center comes to a focus at different points inside the telescope.

B. The light of different colors comes to a focus at different points inside the telescope.

C. Light reflecting from the sides of the telescope comes to a focus at different points inside the telescope.

D. The objective lens varies in thickness from center to edge, and light passing through these different thicknesses suffers different amounts of absorption.


30. Who developed the first reflecting astronomical telescope?

A. Ptolemy

B. Newton

C. Galileo

D. Copernicus


31. Which substance in Earth's atmosphere is the main absorber of infrared radiation from space?

A. ozone

B. carbon dioxide

C. water vapor

D. methane


32. Which of the following colors for a star corresponds the highest surface temperature?

A. red

B. white

C. blue

D. yellow


33. Ionization of an atom occurs when

A. the nucleus breaks apart

B. an electron is removed from the atom.

C. an electron is lifted from the ground state to an excited level.

D. an electron is allowed to return to the ground state.


34. In the scientific method, what step come before tests?

A. hypotheses

B. predictions

C. beliefs

D. observations


35. How many fundamental forces are there in nature?

A. 4

B. 1

C. 2

D. 3


36. A light bulb produces

A. a continuous spectrum

B. an emission or an absorption spectrum depending on its brightness

C. an absorption spectrum

D. an emission spectrum


37. According to Newton's 1st Law of Motion, if a body is traveling on a curved path we know for sure that

A. its speed must be changing

B. no force is acting

C. its velocity is constant

D. a force must be acting


38. According to Stefan's and Wien's radiation Laws a hot object will give off

A. less radiation and at shorter wavelengths than a cool object

B. more radiation and at longer wavelengths than a cool object

C. less radiation and at longer wavelengths than a cool object

D. more radiation and at shorter wavelengths than a cool object


39. If you are on Earth and are located in the darkest part of the Moon's shadow you will see a

A. penumbral lunar eclipse

B. total lunar eclipse

C. partial solar eclipse

D. total solar eclipse


40. Sunburn is associated with which kind of electromagnetic radiation?

A. ultraviolet (UV)

B. infrared (IR)

C. microwaves

D. X-rays


41. The main optical element in a refracting telescope is a

A. lens.

B. mirror.

C. combination of many small plane mirrors.

D. prism of glass.


42. The major reason astronomers seek funds to build larger telescopes is to

A. bring stars closer to Earth.

B. measure a wider spectrum of light from stars.

C. provide magnified images of stars.

D. collect more light from distant objects.


43. In the reflection of a beam of light from a flat surface, the relationship between the angle of incidence i between the perpendicular to the surface and the incident beam and the angle of reflection r between the perpendicular and the reflected beam is

A. r is equal to 2i.

B. The reflected ray always follows the perpendicular direction from the reflecting surface.

C. r is equal to i/2.

D. r is equal to i.


44. In the electromagnetic spectrum visible light occupies what proportion of the complete range?

A. about half the possible range

B. two narrow but separate ranges between ultraviolet and infrared radiation, the red and the blue, which mix to give all the other colors

C. a very narrow range

D. almost the full range between radio and X rays


45. The temperature of a gas cloud in space is directly related to and representative of the

A. number of atomic collisions per second within the cloud.

B. average speed of its atoms.

C. density of the cloud.

D. color of the cloud.

46. A typical but very cool star might have a temperature of 3100C. On the Kelvin scale, this is about

A. 2827 K.

B. 3068 K.

C. 3373 K.

D. 3100 K.


47. In its interaction with matter, light behaves

A. only as waves.

B. alternatively as particles or as waves, switching its properties about once every second.

C. as both waves and particles, depending on the experiment.

D. only as particles.


48. The overall diameter of a typical atom is about

A. 10-7 m

B. 10-5 m

C. 10-14 m

D. 10-10 m


49. How many neutrons are there in the nucleus of the isotope 18O of oxygen (which has Z = 8)?

A. 8

B. 18

C. 9

D. 10


50. The word planet is derived from a Greek term meaning

A. astrological sign.

B. non-twinkling star.

C. bright nighttime object.

D. wanderer.


Answer Key:

01-10: B B C D D D C B A D

11-20: A B D B B D D C B B

21-30: A C C A B C D A B B

21-40: C C B B A A D D D A

41-50: A D D C B C C D D D