planetary motion

Newton's second law describes an object's

• accelleration

• momentum

• inertia

• velocity

Kepler's Three Laws of Planetary motion helped proved the ___________ model of the solar system

• Ptolemiac

• Copernican

• Newtonian

• Jacksonian

Kepler studied the orbit of which planet?

• Mars

• Jupiter

• Venus

• Mercury

Newton realized the force that holds the planets in orbit was

• electromagnetic radiation

• electricity

• gravity

• inertia

An ellipse that is a perfect circle will have an eccentricity with the value

• 0

• 1

• .5

• .1

a planet orbiting the Sun is traveling the fastest at its

• perihelion

• aphelion

• the speed of planets is constant

• the planets are always slowing down

Kepler's Third Law is made up of which two variables? (mark all that apply)

• time

• distance

• velocity

• acceleration

All ellipses have have eccentricity value that falls between what two numbers?

• 0,1

• 0,10

• 1,10

• 1,100

The orbit of the planet ___________________ was difficult for early astronomers to understand because it orbits the sun with high eccentricity.

• earth

• venus

• Mars

• jupiter

during their orbits planets always

• slow down

• speed up

• accellerate

• move at a constant speed