Midterm Review - Part 2

If a galaxy were approaching Earth, the wavelength of light produced by the star would increase while the frequency would decrease.

• True

• False

Answer explanation

According to the Doppler Effect, the wavelength DECREASES as waves approach, and the frequency INCREASES.

Tags

NGSS.HS-PS4-1

Astronomers study the spectra of stars to determine their composition. According to the spectra below, what are some of the elements that make up the sun’s atmosphere? Choose all that apply.

• Sodium

• Calcium

• Hydrogen

• Helium

• Mercury

Answer explanation

Match the lines in the spectrum for each element to the Sun.

Tags

NGSS.MS-PS1-1

A student creates a model by placing raisins in bread dough and allowing the dough to rise for several hours. The student sketches the model before and after the dough rises. The student claims that the model accurately describes the motion of the galaxies in the universe. What evidence from the model supports the student’s claim?

• As the dough rises, the size of the raisins increases, resembling the expansion of the galaxies

• As the dough rises, the distance between the raisins decreases, indicating that the galaxies will collide.

• As the dough rises, the size of the raisins decreases, resembling the emission of light from stars.

• As the dough rises, the distance between the raisins increases, indicating the galaxies are moving apart.

Answer explanation

The galaxies (raisins) are moving away from each other, but they are not changing size/shape.

Tags

NGSS.MS-PS2-4

NGSS.MS-ESS1-2

The graph shows the velocities and distances from Earth for several galaxies in the universe. What can be concluded from the graph?

• The closer the galaxy, the faster it moves towards Earth.

• The closer the galaxy, the slower it moves towards Earth.

• The farther the galaxy, the faster it moves away from Earth.

• The farther the galaxy, the slower it moves away from Earth.

Answer explanation

Galaxies are mostly moving away from Earth. The farther the galaxy, the faster it is moving.

Tags

NGSS.MS-PS3-1

Which of the following TWO statements best summarizes the evidence that explains how the universe formed from a point of singularity?

• The space between galaxies is continuing to expand, as demonstrated by their redshift in relation to Earth.

• The universe is currently collapsing, since most galaxies are in blueshift and coming closer to the Milky Way.

• Cosmic background radiation can still be detected and traced back to a singular point of origin.

• The universe is static – meaning that it is not changing and we do not have any evidence to support that it has changed over the course of human history.

Answer explanation

The pieces of evidence that support the theory of rapid expansion are 1) redshift 2) CBR and 3) abundance of hydrogen and helium in the universe.

Tags

NGSS.HS-ESS1-2

According to the Doppler Effect, which galaxy, A or B, is in redshift?

• A

• B

• Both

• Neither

Answer explanation

Redshift is when the spectral lines are shifted toward the red end of the EM spectrum. This indicates a body is moving away from Earth.

Tags

NGSS.HS-ESS1-2

When the solar system was very young, the sun was just being formed and planets had not yet been made. The solar system was mostly gas and dust. Which statement best explains how planets formed in the early solar system?

• Planets formed from magnetism in space that interacted with light from the stars.

• Planets formed from nebulas (gas and dust) that are pulled together because of gravity.

• Planets formed from large asteroids that had broken apart.

• Planets formed from molten metal in volcanic eruptions.

Answer explanation

Gravity was the driving factor behind the formation of the solar system.

The Earth revolves around the Sun due to the gravitational attraction between the Sun and Earth. How would the Earth move if suddenly there was no gravitation attraction between the Earth and Sun?

• Earth would continue to move in its same orbital path because of its inertia.

• Earth would move in a straight line because there would be no gravity to oppose its inertia.

• Earth would stop moving without the Sun’s gravitational pull.

• Earth would reverse its path because the Sun’s gravity would no longer pull Earth toward it.

Answer explanation

If the centripetal force of gravity is removed, Earth will move in a straight line indefinitely.

Tags

NGSS.MS-PS2-4

NGSS.MS-ESS1-2

A student reads that the force of gravity between two objects depends on the size of each object and the distance between them. What can the student infer about the velocity experienced by planets in the solar system based on the reading?

• The force of gravity exerted by the Sun is different for each planet, causing the larger planets to move closer to the Sun than the smaller planets.

• The force of gravity exerted by the Sun is different for each planet, causing the smaller planets to move closer to the Sun than the larger planets.

• The force of gravity exerted by the Sun is different for each planet, causing the planets closest to the Sun to revolve faster than the planets farthest from the Sun.

• The force of gravity exerted by the Sun is different for each planet, causing the planets farthest from the Sun to revolve faster than the planets closest to the Sun.

Answer explanation

Objects that are closer to the sun experience a stronger gravitational attraction and will revolve faster.

Tags

NGSS.MS-PS2-4

NGSS.MS-ESS1-2

The strength of a gravitational force between two objects depends on which two factors?

• Mass

• Shape

• Velocity

• Density

• Distance

Answer explanation

Gravity depends on mass and distance between two objects.

Tags

NGSS.MS-PS2-4

NGSS.MS-PS2-2