CSET CSET Science: Earth and Space Sciences 3

Question 1

What is the primary energy source that powers the Sun?

Accepted Answer

Nuclear fusion of hydrogen nuclei into helium

Answer

Chemical combustion of hydrogen gas

Answer

Gravitational compression of stellar material

Answer

Nuclear fission of heavy radioactive elements

Question 2

What does the Hertzsprung-Russell (H-R) diagram plot?

Accepted Answer

Stellar luminosity versus surface temperature

Answer

Positions of stars within a constellation

Answer

Timeline of stellar formation in the Milky Way

Answer

Distances of stars from Earth versus their mass

Question 3

According to current scientific understanding, what is the approximate age of the universe?

Accepted Answer

13.8 billion years

Answer

4.5 billion years

Answer

100 billion years

Answer

4.5 trillion years

Question 4

What causes the phases of the Moon as observed from Earth?

Accepted Answer

The changing angle from which observers on Earth view the sunlit half of the Moon

Answer

Earth's shadow blocking sunlight from reaching the Moon

Answer

The Moon passing through Earth's shadow during its orbit

Answer

Variations in the Moon's distance from Earth during its elliptical orbit

Question 5

Which type of galaxy is characterized by a central bulge surrounded by a flat rotating disk with spiral arms?

Accepted Answer

Spiral galaxy

Answer

Elliptical galaxy

Answer

Irregular galaxy

Answer

Lenticular galaxy

Question 6

What causes a solar eclipse?

Accepted Answer

The Moon passes directly between Earth and the Sun

Answer

Earth passes directly between the Sun and the Moon

Answer

Earth's shadow falls on the surface of the Moon

Answer

The Moon moves to the far side of Earth, away from the Sun

Question 7

Kepler's Third Law of planetary motion states that:

Accepted Answer

The square of a planet's orbital period is proportional to the cube of its semi-major axis

Answer

Planets move in elliptical orbits with the Sun at one focus

Answer

A line from a planet to the Sun sweeps equal areas in equal times

Answer

Gravitational force between two bodies decreases with the square of the distance between them