Earth's Solar System Ch. 6

Which of these statements best describes a heliocentric model?

• The sun and the planets orbit Earth.

• Earth is the center of the universe.

• The planetary orbits are nearly circular.

• All the planets and smaller objects orbit the sun.

What are two factors that combine to keep the planets in orbit around the sun?

• mass and inertia

• gravity and inertia

• gravity and orbital path

• inertia and orbital path.

What is the tendency of an object to resist a change in motion/

• weight

• gravity

• inertia

• orbital velocity

The solar system formed from

• an expanding galaxy

• a giant cloud of gas and dust

• an enormous explosion

• a black hole

starting from the sun's center, what is the order of layers in the sun's interior/

• core, convection zone, radiation zone

• radiation zone, core, convection zone

• core, radiation zone, convection zone

• convection zone, radiation zone, core

which part of the sun can be seen only during a total eclipse/

• sunspots

• the corona

• the photosphere

• solar prominences

Besides being in orbit around the sun, what other characteristics must an object have to be a dwarf planet?

• It is made of rock and metal.

• It is found between the orbits of Jupiter and Mars.

• It is round and has cleared its region of space.

• It is a loose ball of rock and ice and has a long narrow orbit.

An astronomical unit (AU) is based on the average distance between which two objects in the solar system?

• Neptune and the sun

• earth and the sun

• earth and the moon

• the sun and the moon

Nicolaus Copernicus and Galileo Galilei were both astronomers that developed models of the solar system. How are the Copernican and Galilean models of the solar system alike?

• Both have moons that orbit different planets.

• Both have Earth at the center of the solar system.

• Both have the sun at the center of the solar system

• Both have planets with orbits that are shaped like ellipses.

One factor determining the planet's orbit is the planet's inertia. What force acts on a planet, causing the planet to move in an elliptical path rather than a straight line?

• friction

• gravity

• magnetism

• all of these