Unit 1 Flashcards
(28 cards)
Kepler’s Laws of planetary motion are based on detailed observations made by which astronomer:
Tycho Brahe
Which of the following astronomers first proposed the heliocentric model of the solar system?
Nicholas Copernicus
- Which of Galileo’s discoveries provided the greatest evidence that the Sun must be at the center of the solar system?
that Venus goes through phases
- Which of the following is NOT a fundamental difference between the geocentric and Sun-centered models of the solar system?
d. The geocentric model is useless for predicting planetary positions in the sky, while even the earliest Sun-centered models worked almost perfectly.
- Kepler’s second law says “a line joining a planet and the Sun sweeps out equal areas in equal amounts of time.” Which of the following statements means nearly the same thing?
Planets move farther in each unit of time when they are closer to the Sun.
- Imagine that you throw a ball directly upward. Which of the following statements best describes how Newton’s Second Law accounts for the motion of the ball when it reaches its maximum height?
The ball has a net force that is downward and an acceleration that is downward.
- Which of the following would cause the force on the Moon by the Earth to increase by the largest amount?
move the moon two times closer to Earth.
Kepler’s 1st Law
orbits are elliptical
Kepler’s 2nd Law
Planets travel faster when closer to Sun than when they are farther away. The planets sweep out equal areas in equal amounts of time.
Kepler’s 3rd Law
Planets that have larger orbits have longer years. The orbital distance and length of year do not depend upon mass of the planet
Newton’s 1st Law
Objects in motion tend to stay in motion unless there is an outside unbalanced force
Newton’s 2nd Law
F=ma
Newton’s 3rd Law
For every action there is an opposite and equal reaction
Universal Law of Gravitation
Force of gravity is between two objects. The strength of the gravitational force depends on two things- 1) the mass of the objects, and 2) the distance between the objects. Bigger masses mean stronger gravitational force. Objects closer together have a stronger gravitational force than objects that are farther apart.
The great scientist ___ made discoveries that strongly supported a heliocentric cosmogony
Galilio (1564-1642, Italian, blind at death, labeled heretic)
Known for first observations of the sun
Galileo
____’s telescope revealed that Jupiter had moons which orbited Jupiter instead of Earth
Galileo
Created first theoretical model for explaining gravity
Isaac Newton (1642-1727, British)
____ always comes in pairs
Force
What people were the first to make models of nature?
Greeks
____ measured the size of Earth by observing the angle at which the Sun’s rays hit our planet’s surface.
Eratosthenes
Underpinnings of Greek geocentric model
Earth at center of universe; heavens must be “perfect”, Objects moving on perfect spheres or in perfect circles
most sophisticated geocentric model was that of ___
Ptolemy (AD 100-170)
A cleric and scientist who played a leading role in the emergence of modern science. Although, he could not prove the Earth revolves around the Sun, he presented such compelling arguments for this idea that he turned the tide of cosmological though and laid the foundations for Galileo/Kepler
Nicoulas Copernicus
