Review for Unit 3: Nature of Orbits

The diagram below represents planets A and B, of equal mass, revolving around a star. Compared to planet A, planet B has a

• weaker gravitational attraction to the star and a shorter period of revolution

• weaker gravitational attraction to the star and a longer period of revolution

• stronger gravitational attraction to the star and a shorter period of revolution

• stronger gravitational attraction to the star and a longer period of revolution

Answer explanation

Planet B, being farther from the star, experiences weaker gravitational attraction and thus has a longer period of revolution compared to planet A, which is closer to the star.

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

Approximately how many times larger is the diameter of the sun compared to Venus?

• 10 times

• 100 times

• 1000 times

• 10,000 times

Answer explanation

The diameter of the Sun is about 1.4 million kilometers, while Venus has a diameter of about 12,104 kilometers. Dividing these gives approximately 116 times, so the Sun's diameter is roughly 100 times larger than Venus.

Tags

NGSS.MS-ESS1-3

Which planet has the greatest axial tilt?

• Jupiter

• Earth

• Uranus

• Venus

Answer explanation

Uranus has the greatest axial tilt of 98 degrees, but the question asks for the greatest tilt among the options provided. Venus has a significant tilt of about 177.4 degrees, making it the correct answer.

What is Earth's approximate rate of movement per day?

• 15 degrees per hour

• 1 degree per hour

• 24 degrees per hour

• 360 degrees per day

Answer explanation

Earth rotates approximately 15 degrees per hour, which totals 360 degrees in 24 hours. This means that in one day, Earth completes a full rotation, making 15 degrees per hour the correct answer.

What is Earth's approximate rate of movement along its orbit?

• 1° per day

• 1° per hour

• 15° per day

• 15° per hour

Answer explanation

Earth moves approximately 1° per day along its orbit around the Sun. This slow movement is due to the vast distance it travels in its elliptical orbit, making 1° per day the correct rate.

Which planet's day (period of rotation) is longer than its year (period of revolution)?

• Mercury

• Venus

• Jupiter

• Saturn

Answer explanation

Venus has a rotation period of about 243 Earth days, while its revolution period around the Sun is about 225 Earth days. This makes Venus's day longer than its year, unlike the other options.

Compared to the orbit of the Jovian planets, the orbit of Halley's comet is

• less elliptical, with a shorter distance between its foci

• less elliptical, with a greater distance between its foci

• more elliptical, with a shorter distance between its foci

• more elliptical, with a greater distance between its foci

Answer explanation

Halley's comet has a highly elliptical orbit, meaning it is stretched out more than the orbits of the Jovian planets. This results in a greater distance between its foci, making the correct choice 'more elliptical, with a greater distance between its foci'.

Tags

NGSS.MS-ESS1-3

Compared to the velocity of Jupiter in its orbit, the velocity of Halley's comet is

• always less

• always greater

• always the same

• sometimes less and sometimes greater

Answer explanation

Halley's comet travels in a highly elliptical orbit, causing its velocity to vary significantly. At times, it moves faster than Jupiter, especially when close to the Sun, and at other times, it moves slower, making the correct answer 'sometimes less and sometimes greater'.

Which sequence lists the Jovian planets in order of increasing mass?

• Jupiter, Saturn, Neptune, Uranus

• Uranus, Neptune, Saturn, Jupiter

• Jupiter, Saturn, Uranus, Neptune

• Neptune, Uranus, Saturn, Jupiter

Answer explanation

The correct order of the Jovian planets by increasing mass is Uranus, Neptune, Saturn, and then Jupiter. Jupiter is the most massive, while Uranus and Neptune are less massive than Saturn.

Which sequence lists the Terrestrial planets in order of increasing mass?

• Mercury, Venus, Earth, Mars

• Mercury, Mars, Venus, Earth

• Mars, Earth, Venus, Mercury

• Earth, Venus, Mars, Mercury

Answer explanation

The correct order of the Terrestrial planets by increasing mass is Mercury, Mars, Venus, Earth. Mercury is the lightest, followed by Mars, then Venus, and Earth is the heaviest.