1. GENERAL SCIENCE MIKE ST. JOHN MIKE ST. JOHN WEEK ONE WEEK ONE

2. Erathostenes BORN 275BC DIED 194 BC BORN 275BC DIED 194 BC CALCULATED THE CIRCUMFERENCE OF THE EARTH TO BE 39000 KM COMPARED TO ACTUAL OF 40075 KM %ERROR OF 2.7% CALCULATED THE CIRCUMFERENCE OF THE EARTH TO BE 39000 KM COMPARED TO ACTUAL OF 40075 KM %ERROR OF 2.7%

3. 804.65 km

5. The Formula Used D = A D = A d = distance between d a Syene and Alexandria A = 360 degrees a = shadow angle of vertical stick D = circumference of the earth (to be determined)

6. Ptolemy 87 – 150 AD

7. Eccentric

8. Epicycle

9. Planetary Model

10. Ptolemaic Universe

12. Copernicus 1473-1543

13. There is no one centre in the universe. There is no one centre in the universe. The Earth's centre is not the centre of the universe. The Earth's centre is not the centre of the universe. The centre of the universe is near the sun. The centre of the universe is near the sun. Little Commentary

14. Commentary Continued The distance from the Earth to the sun is imperceptible compared with the distance to the stars. The distance from the Earth to the sun is imperceptible compared with the distance to the stars. The rotation of the Earth accounts for the apparent daily rotation of the stars. The rotation of the Earth accounts for the apparent daily rotation of the stars.

15. Continued The apparent annual cycle of movements of the sun is caused by the Earth revolving round it. The apparent annual cycle of movements of the sun is caused by the Earth revolving round it. The apparent retrograde motion of the planets is caused by the motion of the Earth from which one observes. The apparent retrograde motion of the planets is caused by the motion of the Earth from which one observes.

16. Data on Planetary Orbits

17. Copernican Universe

19. Tycho Brahe 1546 - 1601

20. Sextant

21. Mural Quadrant

22. Tychonic Universe

23. Johannes Kepler 1571-1630

24. Kepler’s Laws I. The orbits of the planets are ellipses, with the Sun at one focus of the ellipse. I. The orbits of the planets are ellipses, with the Sun at one focus of the ellipse. II. The line joining the planet to the Sun sweeps out equal areas in equal times as the planet travels around the ellipse. II. The line joining the planet to the Sun sweeps out equal areas in equal times as the planet travels around the ellipse.

25. Kepler’s Laws III. The ratio of the squares of the revolutionary periods for two planets is equal to the ratio of the cubes of their semimajor axes: III. The ratio of the squares of the revolutionary periods for two planets is equal to the ratio of the cubes of their semimajor axes:

26. Kepler’s First Law focus

27. Kepler’s Second Law EQUAL AREAS IN EQUAL TIME

28. Kepler’s Third Law

29. Galileo Galilei 1564-1642

30. Sector

31. Telescope

32. Moon

33. Saturn

34. Galileo and Gravity Legend has it that Galileo went to the Tower of Pisa to test Gravity. The experiment which would hit the ground first the heavier or lighter cannonball

35. Gravity Galileo reasoned that gravity must accelerate an object at a constant rate. He conducted experiments to test this hypothesis. This time he used a very long ramp and a ball. Galileo reasoned that gravity must accelerate an object at a constant rate. He conducted experiments to test this hypothesis. This time he used a very long ramp and a ball.

36. Galileo Gravity Demonstrator Galileo thought that it would take twice as long for the ball to roll down the whole ramp as it would from the quarter mark. Galileo thought that it would take twice as long for the ball to roll down the whole ramp as it would from the quarter mark.

37. Mathematics The Language of Science Scientist use metric units in their calculations Scientist use metric units in their calculations Basic Measurement Units are: Basic Measurement Units are: Mass:kilograms Mass:kilograms Length:meters Length:meters Time:seconds Time:seconds

38. Scalar Versus Vector Scalar quantity just has magnitude Scalar quantity just has magnitude Examples:50 mph8 meters Examples:50 mph8 meters Vector quantity has both magnitude and direction Vector quantity has both magnitude and direction Examples:50 mph in a Northerly Direction 8 meters South Examples:50 mph in a Northerly Direction 8 meters South

39. Isaac Newton 1642 -1727 “If I have been able to see further, it was only because I stood on the shoulders of giants.” — Sir Isaac Newton “If I have been able to see further, it was only because I stood on the shoulders of giants.” — Sir Isaac Newton

40. Newton’s First Law of Motion An object at rest will stay at rest an object in motion will stay in motion unless acted upon by a force.That property about the object that resist motion is called inertia. An object at rest will stay at rest an object in motion will stay in motion unless acted upon by a force.That property about the object that resist motion is called inertia.

41. Newton’s Second Law of Motion Force = (mass) (acceleration) or F=ma Force = (mass) (acceleration) or F=ma Units:masskilograms accelerationm/s 2 ForceNewtons Units:masskilograms accelerationm/s 2 ForceNewtons

42. Newton’s Third Law of Motion For every action there is an equal and opposite reaction. For every action there is an equal and opposite reaction.

43. Which Will Hit the Ground First? Motion in the x and y direction are independent. The key is that both objects started at the same height above the ground. Motion in the x and y direction are independent. The key is that both objects started at the same height above the ground.

44. Newton and Gravity Newton thought that the same force that causes an apple to fall to the ground is the same as the force that keeps the moon orbiting the earth. Newton thought that the same force that causes an apple to fall to the ground is the same as the force that keeps the moon orbiting the earth.

45. Newton’s Universal Law of Gravitation F = G m 1 m 2 d 2 F = G m 1 m 2 d 2 F: Force F: Force G: Gravitational Constant G: Gravitational Constant m 1 : mass of first object m 1 : mass of first object m 2 : mass of second object m 2 : mass of second object d: distance between the objects d: distance between the objects

46. How Much is the Force of Attraction between the Sun and the Earth? 2x10 30 kg 6x10 24 kg1.5x10 10 m F = (6.67x10 -11 Nm 2 /kg 2 ) (2x10 30 kg) (6x10 24 kg) (1.5x10 10 m) 2 F = 3.56x10 24 Newtons