PHY 102 1nd Edition Exam 1 Study Guide Lectures 1 11 Lecture 1 What is included in the outside world Celestial sun moon stars regular predictable you can count on it Terrestrial trees mountains rivers animals close tamable knowable good but not as good as celestial In between rain snow hurricane tornado always moving Who were the first scientists Priests What explains observation Theory abandon theory if observation is wrong What was Pythagoras s theory and why didn t it stick All planets stars moon and earth move uniformly around a central fire not the sun on circular paths Parallax change in the line of sight Pythagoras could not detect the earth s motion What was Plato s theory and what did he discover Everything moves around the earth Planets do not move uniformly What is retrograde motion Change in direction What was Eudoxos s theory Planet is attached to one uniformly rotating sphere attached to another uniformly rotating sphere etc Lecture 2 What does Eudoxos mean when he says all spheres are concentric with the earth Distance between planet and earth is fixed What did Aristarchus study and what did he figure out Moon and Sun The moon is 1 3 33 of the size of the earth improvement 27 Distance to the moon is about 25 times Earth s diameter improvement 30x Earth to sun distance is about 20 times the earth to moon distance The sun is 7 times the size of the earth Discovered heliocentrism 1800 years before Copernicus What did Eratosthenes study Earth How big is the earth Circumference 25 000 miles Radius 3 978 miles Lecture 3 What was Apollonius responsible for Explaining retrograde motion as well as change in brightness through epicycles Instead of concentric circles in the homocentric model put the planet on a circle epicycle and let it move on a larger circle deferent What was Ptolemy s theory that lasted 1400 years All planets needed more than one epicycle to account for their motion Geocentric epicycle after epicycle Lecture 4 What did Nicolaus Copernicus discover after Aristarchus Heliocentrism he placed the sun at the center of the universe What did Brache discover Heliocentric and geocentric models were wrong but said to improve on the better one heliocentric What are Kepler s three laws of planetary motion 1 Each planet moves on an ellipse with the sun at one of its foci 2 The planet sweeps equal areas in equal time intervals planets move faster when closer to the sun 3 T2 ka3 or T1 T2 2 a1 a2 3 Lecture 5 SNOW DAY Lecture 6 BLUE BOOK PROBLEMS Lecture 7 What is rectilinear motion The simplest form of motion Displacement velocity acceleration describe this motion What is the simplest form of rectilinear motion Uniform motion velocity does not change x vt What is acceleration Change in velocity time a v t v can be positive or negative What is uniformly accelerated motion Acceleration does not change v at vo x vot at2 Lecture 8 How is motion described In relation to an observer Observer is not moving object moves relative to observer What is the difference between average velocity and average speed Average velocity is a vector arrow and average speed is distance Lecture 9 What is Aristotle s observation of motion that was proven completely wrong All moving objects are being pushed or pulled Who is Galileo The father of modern science What is underdetermination Infinite theories and each theory is as valid as the other s The truth of no theory or statement can be determined How does a wood block sliding down an incline describe Galileo s first law of motion On an infinitely smooth horizontal surface an object needs no push or pull to move Lecture 10 What does the first law of motion also state The momentum of an isolated system does not change What is the key formula to know for the first law p mv p is momentum m is mass v is velocity unit for p is kg m s Lecture 11 What is the formula for the second law of motion Fnet ma F is force Unit for F is Newtons N What are the two types of forces 1 Contact push pull friction drag 2 Action at a distance gravity What is the difference between normal force and friction force Normal balances gravity coming from the earth Friction opposite direction of motion