Chapter 4 Flashcards
Newton’s First Law
An object in motion will continue in motion unless acted on by an outside force
relationship between Tycho and Kepler
Kepler worked for Tycho
Virtually no one acknowledged Kepler’s work during his lifetime
true
The key observation of Venus was that it exhibited
gibbous phase
A complete physical theory to explain the motion of the planets was developed by
Newton
The idea that planets do not move at constant speeds in their orbits can be attributed to
Kepler
Galileo’s final punishment for his disagreement with the Catholic Church
He was placed under house arrest for life
The first proof that the Earth orbits the Sun was provided by
Galileo’s observation of the phases of Venus
Gravity between two objects is __________ proportional to the product of their masses and __________ proportional to the square of the distance between them
directly, indirectly
Kepler’s First Law
Planets move in ellipses with the Sun at one focus
Galileo discovered
Moons of Jupiter
changing sizes and phases of Venus
craters and mountains on the moon
sunspots on the sun
non-uniform shape of Saturn
millions of stars in the Milky Way
Kepler second law
line from planet to sun sweeps out equal areas in equal amounts of time
Perihelion
point at which elliptical orbit is closet to the sun
Aphelion
point at which elliptical orbit is furthest from the sun
Kepler third law
period of a planets orbit squared is proportioned to its average distance from the sun cubed
