Astronomy Final Exam: Chapters 5 & 6 Flashcards
How was Galileo’s conclusions different from Aristotle’s conclusions?
Aristotle said all things things fall at a constant rate & Galileo said things fall w/ an increasing speed of 9.8 m/s no matter the weight
What is the universal mutual gravity theory?
States that gravity of one object that pulls on another object is equal to the other object’s gravity on the one object
What is the is the Inverse Square Law?
Gravity is weaker at greater distances & strength would decrease as the square of the distance increased
What are Newton’s Laws?
1.) A body continues at rest or uniform motion in a straight line unless acted on by an external force
2.) The acceleration of a body is inversely proportional to its mass, directly proportional to the force, & in the same direction as the force (F = ma)
-For every action, there is an equal but opposite reaction
What is velocity?
Speed w/ specific direction
What is acceleration?
Direction & speed changes
What is momentum?
How an object continues to move after force is applied (measures motion)
What is momentum’s formula?
velocity x mass
What is kinetic energy?
The energy of movement or motion
What do the tides do?
Pull at the Moon at the near & far side
What are orbits centered around?
Mass
What is a geosynchronous orbit?
Astronomical body orbiting a satellite
What happens to an object if it were orbiting earth?
Actually being accelerated (falling) towards Earth’s center
What is escape velocity?
Required to escape an astronomical unit
What is orbital velocity?
Velocity / gravity pulling at you in space (constant / always happening)
What is the problems with Aristotle’s retrograde motion model?
This model does not account for planets growing dimmer / brighter in the sky
Does the speed of light change?
No, it is constant
What is the equivalence principle?
Observers cannot distinguish locally between inertial forces due to acceleration vs. uniform gravitational forces due to the presence of a massive body
What is gravity caused by?
The curvature of spacetime
What does mass depend on?
Velocity
Who was the earliest astronomer?
Copernicus
Who were the middle astronomers?
-Kepler
-Brahe
-Galileo
Who was the latest astronomer?
Newton
What is the electromagnetic spectrum?
An array of electromagnetic radiation displayed in order of wavelength
What are the wavelengths order from shortest to longest?
Gamma Rays, X-rays, UV, Visible, Infrared, Microwaves, & Radiowaves
What are refracting telescopes?
Uses a lens to gather & focus light using a primary lens
Who used refracting telescopes?
Galileo
Who used reflecting telescopes?
Newton
What are reflecting telescopes?
Uses a mirror to focus light using a primary mirror
