Motion in Space

The diagram below is a basic model of the orbits of Mercury and Venus.

Which dotted line indicates the force that plays the largest role in Mercury's orbit?

• W, the gravitational force of the Sun

• X, the force of Mercury's motion

• Y, the gravitational force of Venus

• Z, the force of friction from other matter

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

Scientific knowledge changes over time due to old theories being replaced by new theories. Revisions are made as new knowledge becomes available. Consider the geocentric theory of Earth which was once accepted as an explanation of how objects were positioned in our solar system. Which statement best explains this theory?

• The Sun is considered to be the center of the universe.

• The orbits of the planets are elliptical and not circular.

• The Sun is considered to be the center of revolving planets and stars.

• Earth is considered to be the center of the revolving planets and the stars.

A group of students listed the factors that they thought affected the strength of the gravitational force between the Sun and any one of its planets. Which of these items belongs on the list?

I. The mass of the Sun

II. The mass of the planet

III. The distance between the Sun and the planet

IV. The time it takes the planet to revolve around the Sun

• II only

• IV only

• I and III only

• I, II, and III only

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

Which of the following statements describes a belief of those who supported the geocentric theory of the solar system?

• Planetary orbits are elliptical.

• Stars revolve around the Sun.

• The Sun revolves around Earth.

• The stars and planets evolve over time.

Mr. Luna asked his science class to work in groups to compare the heliocentric and geocentric models of the solar system. The students developed the chart shown below.

Which group provided answers that most accurately compared the models?

• Group 1

• Group 2

• Group 3

• Group 4

Tags

NGSS.MS-ESS1-1

Scientists believe that before the Solar System formed, it was a nebula, or cloud of gas and dust, which slowly began to become concentrated and rotate.

Which force is responsible for causing the formation of the Solar System?

• electricity

• friction

• gravity

• magnetism

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

Which force prevents the planets from drifting away from the Sun?

• inertial force

• nuclear force

• centrifugal force

• gravitational force

Tags

NGSS.MS-ESS1-2

NGSS.MS-PS2-4

NGSS.MS-PS2-5

Many scientists have presented models to explain planetary motion and position in our solar system. Use the chart below to answer the question.

What was a major reason for Kepler's model to replace Copernicus's model over time?

• irregularities with the motion of the Sun

• irregularities with the motion of asteroids

• irregularities with the motion of the Moon

• irregularities with the motion of the planets

Tags

NGSS.MS-PS2-4

Which statement describes a difference between the geocentric model and the heliocentric model of the solar system?

• The geocentric model states that planetary orbits are circular, and the heliocentric model states that they are elliptical.

• The geocentric model states that planetary orbits are elliptical, and the heliocentric model states they are circular.

• The geocentric model states that Earth is moving, and the heliocentric model states that Earth is stationary.

• The heliocentric model states that both the Sun and the Moon orbit Earth, and the geocentric model states that only the Moon orbits Earth.

Early astronomers described the solar system as being geocentric, meaning that Earth was the center of the universe and all other bodies moved around it. Later, in the 17th century, Nicolaus Copernicus developed a heliocentric model. The heliocentric model stated that the Sun is the center of the universe.

Which observation was especially problematic for the geocentric model of the solar system?

• the rotation of the planets

• the revolution of the Moon around Earth

• the movement of the Sun across the daytime sky

• the movements of the visible planets in the night sky

Tags

NGSS.MS-ESS1-1