Latest Physical Science Reviewer 2

1. What part of the atmosphere protects Earth’s surface from harmful ultraviolet radiation?

A. Exosphere

B. Mesosphere

C. Stratosphere

D. Troposphere

Ans: C. Stratosphere

-Ozone is mainly found in the stratosphere. Stratospheric ozone plays a beneficial role by absorbing most of the biologically damaging ultraviolet sunlight, allowing only a small amount to reach the Earth’s surface. The absorption of ultraviolet radiation by ozone creates a source of heat, which actually forms the stratosphere itself.

2. The aurora borealis and aurora australis are caused by interaction between charged particles and Earth’s magnetic field. What layer of Earth’s atmosphere contain these particles?

A. Exosphere

B. Mesosphere

C. Ozonosphere

D. Thermosphere

Ans: D. Thermosphere

-Auroras result from emissions of photons in the thermosphere, from ionized nitrogen atoms regaining an electron and oxygen atoms nitrogen based molecules returning from an excited state to ground state. They are ionized or excited by the collision of particles precipitated into the atmosphere. Both incoming electrons and protons may be involved. Excitation energy is lost within the atmosphere by the emission of a photon, or by collision with another atom or molecules.

3. Which is a deep layer of electrically charged molecules and atoms that reflects radio waves?

A. Exosphere

B. Ionosphere

C. Radiosphere

D. Troposphere

Ans: B. Ionosphere

-The ionized part of the Earth’s atmosphere is known as the ionosphere. Ultraviolet light from the sun collides with atoms in this region knocking electrons loose. This creates ions, or atoms with missing electrons. This is what gives the Ionosphere its name and it is the free electrons that cause the reflection and absorption of radio waves.

4. The Earth completes one revolution around the sun in 365  days. Compared the earth, how long does it take Mercury to complete one revolution?

A. Less than the Earth

B. Greater than the Earth

C. The same as the Earth

D. Cannot be determined

Ans: A. Less than that of the Earth

-It takes Mercury about 88 days to complete one orbit around the sun. This is less than the Earth since Mercury is closer to the sun.

5. What two properties of stars are being directly compared in the Hertzsprung-Russel  Diagram?

I. Size

II. Temperature

III. Luminuosity

IV. Density

A. I and II

B. II and III

C. III and IV

D. I and IV

Ans: B. II and III

-The Hertzsprung-Russell diagram (HR diagram) is one of the most important tools in the study of stellar evolution. Developed independently in the early 1900s by Ejnar Hertzsprung and Henry Norris Russell, it plots the temperature of stars against their luminosity (the theoretical HR diagram), or the color of stars (or spectral type) against their absolute magnitude (the observational HR diagram, also known as a color-magnitude diagram).

6. How is the atmospheric pressure of Mars when compared to the atmospheric pressure of the Earth?

A. Half as much as that of the Earth

B. About the same as the Earth

C. About 1/100^th that of the Earth

D. About 100 times as great as the Earth

Ans: C. About 1/100^th that of the Earth

-The atmosphere of Mars is less than 1% the thickness of Earth’s atmosphere, so it does not protect the planet from the Sun’s radiation nor does it too much to retain heat at the surface. It consists of 95% carbon dioxide, 3% nitrogen, 1.6% argon, and the remainder is trace amounts of oxygen, water vapor, and other gases.

7. Which of the following statements is TRUE for both Saturn and Jupiter?

A. Both rotate faster than the Earth.

B. Both rotate slower than the Earth.

C. Only one rotates rapidly while the rotates very slowly.

D. Their periods of rotation are linked to their period of revolution.

Ans: A. Both rotate faster than the Earth.

-Jupiter is the fastest rotator (spinner) in the solar system. It only takes about 10 hours for Jupiter to rotate once. The length of a day on Saturn is extremely difficult to determine. Saturn’s day was measured at 10 hours 39 minutes and 24 seconds in the ‘80s. Then it was measured at approximately 10 hours 45 minutes and 45 seconds. In 2006, astronomers used more advanced equipment to measure the planets ending up with a measurement of about 10 hours and 47 minutes.

8. According to Kepler’s Law, what is the shape of all orbits of the planets?

A. Ellipse

b. Hyperbola

C. Oblate spheroid

D. Parabola

Ans: A. Ellipse

-Johannes Kepler formulated the Law of Orbits which states that all planets move in elliptical orbit, with the sun at one focus.

9. What is the first successful space rotation program that tested the ability of astronauts to work for long periods and studied their body responses to weightless condition?

A. Apollo 11

B. Sputnik I

C. Salyut

D. US Skylab

Ans: D. US Skylab

-Skylab was the United State’ first space station launched and operated by NASA. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems.

10. The universe is estimated to be between ten and twenty billion years old. This estimate is based on the value of which constants?

A. Speed of light

B. Hubble constant

C. Mass of the Earth

D. Mass of the electron

Ans: B. Hubble Constant

-The Hubble constant is one of the most important numbers in cosmology because it may be used to estimate the size and age of the Universe. It indicates the rate at which the universe is expanding.

11. On which of the following planets would the sun rise in the west?

A. Mars

B. Jupiter

C. Saturn

D. Venus

Ans: D. Venus

-Venus rotates retrograde (east to west) compared with Earth’s prograde (west to east) rotation. Seen from Venus, The sun would rise in the west andset in the east.

12. Which of the following describes an albedo?

A. Brightness of the star

B. Phase changes of a planet

C. Wobbling motion of a planet

D. Amount of light a planet reflects

Ans: D. Amount of light a planet reflects

-Albedo is the fraction of solar energy reflected from the Earth back into space. It is a measure of the reflectivity of the Earth’s surface. Ice, especially with snow on top of it, has a albedo: most sunlight hitting the surface bounces back towards space.

13. Where are most asteroids located?

A. Between Earth and Mars

B. Between Mars and Venus

C. Between Mars and Jupiter

D. Between Jupiter and Saturn

Ans: C. Between Mars and Jupiter

-While there are asteroids all over the solar system, the vast majority of asteroids are grouped in the asteroid belt, which is more like a loose grouping than a belt, and lies between the orbits of Mars and Jupiter. The asteroids are so small and far away that they appears as faint stars, if they even appear at all; no asteroid is bright enough to be seen without some optical aid, except Ceres on its closest approach to Earth.

14. Which refers to the precision of the Earth?

A. Change night to day

B. Earth’ motion around the sun

C. Effect of the moon on the Earth’s orbit

D. Change in orientation of the Earth’s axis

Ans: D. Change in orientation of the Earth’s axis

-In astronomy “precession” refers to any of several slow changes in an astronomical body’s rotational or orbital parameters, and especially to Earth’s precession of the equinoxes.

15. What kind of eclipse do we see when the moon is entirely within the Earth’s umbra shadow?

A. Total solar

B. Total lunar

C. Partial solar

D. Partial lunar

Ans: B. Total lunar

-A lunar eclipse occurs when the Moon passes directly behind the Earth into its umbra (shadow). This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, a lunar eclipse can only occur the night of a full moon.

16. At which phase of the moon do solar eclipses occur?

A. Full moon

B. First quarter

c. New moon

D. Third quarter

Ans: C. New Moon

-A solar eclipse happens during a new moon, when the moon is between Earth ans Sun and the moon blocks out the Sun.

17. If lunar eclipse occurs tonight, when is the soonest  that a solar eclipse can occur?

A. Tomorrow

B. In two weeks

C. In one month

D. In one year

Ans: B. In two weeks

-The shortest possible time between a lunar and solar eclipse is just over 14 days. It happened in April 2005, when the April 8 solar eclipse was followed on April 24 by a penumbral lunar eclipse.

18. Which one is considered as one of the most important results of the Apollo missions to the moon?

A. Discovery of subsurface of water

B. Determination of the age of moon rocks

C. First observations of surface features called craters

D. Proof that craters were produced by volcanic eruptions

Ans: D. Proof that craters were produced by volcanic eruptions

-Before Apollo, the state of the Moon was a subject of almost unlimited speculation. We now know that the Moon is made of rocky material that has been variously melted, erupted, through volcanoes, and crushed by meteorite impacts.

19. What is the problem experienced by astronauts staying for long periods of time aboard the international space station?

A. Weight loss due to diet

B. Determined of the age of moon rocks

C. Muscle loss due to lack of exercise

D. Effects of lower gravity on the body

Ans: D. Effects of lower gravity on the body

-There are many health problems associated with weightlessness. Bones and muscles weaken, and other changes also take place within the body.

20. NASA development a filtration process to make waste water on space flights renewable. Where might this filtration process be used on Earth?

A. In areas where water is salty

B. In areas where water is contaminated

C. In areas where water is used for recreation

D. In areas where water contains hard minerals

Ans: B. In areas where water is contaminated

-Space stations use both physical and chemical processes to remove contaminants, as well as filtration and temperature sterilization to ensure the water is safe to drink. USA is currently developing a biological treatment system that will purify water on future space missions. The microorganisms used in this process destroy contaminants in the water. Same processes might be used on Earth in areas where is contaminated.

To download this reviewer, just click here. Good luck and God bless!