Moon Phases. The moon phases grow from right to le2 in the Northern hemisphere. Moon on the right, ge7ng bigger every night (waxing)

Transcription

1 Moon Phases The moon phases grow from right to le2 in the Northern hemisphere. Moon on the right, ge7ng bigger every night (waxing)

2 Moon Phases When the moon is waning, it is fading to the le2 unbl there s no moon remaining.

3 Moon Phases

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5 RevoluBon versus RotaBon RotaBon means to spin. The earth rotates on its axis. The earth rotates once every 24 hours. RevoluBon means to go around. The earth revolves around the sun once every 365 days.

6 Seasons The Earth is not paralell to the sun. The axis is at an angle (between 22 and 24.5 degrees. Because of the Blt (angle) the sun hits the earth and either the northern or southern hemisphere receives more radiabon.

7 Seasons

8 Seasons

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10 Seasons The hemisphere that is Blted towards the sun will be in summer. The hemisphere Blted away from the sun is in winter Seasons go in order from winter Spring summer Fall (Just like the song!)

11 The Rocky Planets

12 Mercury Smallest axial Blt; less then 1 degree Orbits the sun in 88 days Iron core Cratered surface similar to the moon Smallest planet Rotates slowly (1-1/2 Bmes per revolubon)

13 Venus Axial Blt is 25 degrees Rotates counter clockwise Ho`est planet in the solar system Earth s sister planet

14 Forces and MoBon Gravity Air resistance FricBon AcceleraBon Balanced and Unbalanced Forces Galileo Newton s 3 Laws of MoBon

15 Galileo Galilei ( ) When two objects with different masses are dropped from a height they will land at the same Bme UNLESS a resistant force is present. If there is no resistance both will land at the same Bme. In a vacuum objects fall at the same rate.

16 What forces affect accelerabon? Air resistance the force of air against a moving object Gravity the force of the earth s pull FricBon when two objects rub together energy is lost as heat and slows down the moving object

17 CalculaBng Average Speed Speed is the rate an object moves Speed= total distance traveled Time

18 RelaBve MoBon h`p:// ml_science_share/vis_sim/ mfm05_pg7_relmobon/ mfm05_pg7_relmobon.html

19 How does mass affect speed? Do objects that have greater mass travel faster? Do objects with greater mass drop faster? Which takes more force to move an object with a lot of mass or li`le mass?

20 Warm- up Read secbon 2.1 and 2.2 in secbon C of the book and complete the worksheet.

21 Newton s 3 Laws of MoBon Published in his book in 1695, Isaac Newton described 3 laws of mobon that are the foundabon of the study of physics.

22 Newton s 1 st Law - - InerBa An object at rest will stay at rest unless a force acts upon it. An object in mobon will stay in mobon and in a straight line unless an unbalanced force acts upon it to stop the mobon

23 1 st Law If you are si7ng sbll in your seat on a bus that is travelling at 100 km/hour on a highway, is your body in rest or in mobon? An object will conbnue to move in a straight line. If you are standing on a bus And the bus suddenly moves, Why do you fall backward?

24 Newton s first Law

25 Warm- up What moon phase is this? Is the moon ge7ng bigger or smaller What are three forces that change the rate of accelerabon of an object? How does Newton s first Law explain why your mousetrap car stopped? If a car went 68 meters in 14 seconds, what is it s average speed. Don t forget units/

26 Newton s First Law InerBa The tendency of all objects to resist a change in mobon An object with a small mass has LESS inerba than an object with a large mass. Velocity the speed and direcbon an object is moving. If something changes direcbon, it s velocity changes.

27 Force A Force is a push or a pull

28 Newton s 2 nd Law - - AcceleraBon The accelerabon of an object depends on the mass of the object and the amount of force applied. AcceleraBon is the rate at which an objects speed changes, or if it s direcbon changes OR if it s speed and direcbon changes.

29 AcceleraBon The rate at which velocity changes over Bme Velocity a speed in a specific direcbon

30 Newton s 2 nd Law

31 Newton s 2 nd Law Force = Mass x AcceleraBon What is the accelerabon of a 7 kg mass if a force of 68.6 N is used to move it towards Earth?

32 Newton s 3rd Law AcBon/ReacBon Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first. (For every acbon there is an equal and opposite reacbon)

33 Newton s 3 rd Law SomeBmes, the reacbon force is hard to see

34 Momentum When an object begins to move, it has momentum. The larger the object, the greater the momentum and the more difficult it is to stop. How do Newton s laws explain this?

35 Momentum When an object begins to move, it has momentum. The larger the object, the greater the momentum and the more difficult it is to stop. How do Newton s laws explain this?

36 Balanced and Unbalanced forces If an object is not moving, the forces are balanced. For an object to move OR for an object to stop it must be acted upon by an unbalanced force.

37 Warm- up A rocket takes off. Which of Newton s laws explain the forces? What causes a thrown ball to follow a curved path? A student pushes on an object with 6 N of force and the object does not move. What is the opposing force? What is the difference between velocity and speed? What is the amoung of force required to accelerate a 20 kg object to 5m/s 2?

38 WORK Work is when a force moves an object over a distance Work is measured in Joules W = Force x Distance Simple machines help reduce the amount of force needed to do work.

39 6 Simple Machines: Levers 1 st Class

40 Levers 2 nd class

41 Levers 3 rd Class

42 Inclined Plane

43 Wedge Two inclined planes put together

44 Pulley A pulley reverses the direcbon of the force. Instead of li2ed up, the person pulls down which allows gravity to help.

45 Wheel and Axle

46 Screw An inclined plane wound around a post

47 Mechanical Advantage Machines make work easier by requiring less input force. If a machine provides a MA, the output force is always larger than the input force.

48 5.1 Machines help people do work. When you use a machine to do work, there is always an exchange, or tradeoff, between the force you use and the distance over which you apply that force. You can use less force over a greater distance or a greater force over a shorter distance to do the same amount of work. machine mechanical advantage efficiency SECTION OUTLINE

49 5.2 Six simple machines have many uses.! Simple machines change the size and/or direcbon of a force. simple machine lever Input force Output force fulcrum fulcrum wheel and axle pulley inclined plane wedge screw changes direcgon changes size changes both SECTION OUTLINE

50 5.3 Modern technology uses compound machines. Compound machines are combinabons of simple machines. lever compound machine nanotechnology robot wheel and axle wheel and axle Modern technology creates new uses for machines. Microtechnology and nanotechnology Robots SECTION OUTLINE

51 5.1 Machines help people do work. I. Machines help people do work. A. Machines change the way force is applied. 1. Changing the Size and Distance of a Force 2. Changing the DirecBon of a Force 3. Mechanical Advantage of a Machine B. Work transfers energy. 1. Energy 2. Work C. Output work is always less than input work. 1. Efficiency and Energy 2. Increasing Efficiency machine mechanical advantage efficiency KEY CONCEPT SUMMARY

52 5.2 Six simple machines have many uses.! II. Six simple machines have many uses. A. There are six simple machines. 1. Lever 2. Wheel and Axle 3. Pulley 4. Inclined Plane 5. Wedge 6. Screw simple machine lever fulcrum wheel and axle pulley inclined plane wedge screw B. The mechanical advantage of a machine can be calculated. KEY CONCEPT SUMMARY

53 5.3 Modern technology uses compound machines. III. Modern technology uses compound machines. A. Compound machines are combinabons of simple machines. 1. Gears 2. Mechanical Advantage of Compound Machines B. Modern technology creates new uses for machines. compound machine nanotechnology robot 1. Microtechnology and Nanotechnology 2. Robots KEY CONCEPT SUMMARY

54 Computer AcBvity 1. Go to portaportal.com and log in as a guest Log- in is cesellio` 2. At the bo`om, go to SOL review and select Jefferson Lab. Select middle school science and 40 quesbons. Take the test and pay a`enbon to the quesbons you have trouble with. 3. When you are finished, go to simple machines and pracbce idenbfying them with Ed Head. 4. If you have Bme le2, go to SOL pass and pracbce the secbons you had trouble with on the test.

55 Cart 5 Able, Benjamin 1 ArBs, Raven 2 Baker, Paris 3 Barlow, Tyler 4 Brown, Charles 5 Burton, Marcus 6 Dobalob, Dylan 7 Fleming, Mackenzie 9 Hall, Ryan 10 Hansen, Ariana 11 Ibarra- Balderra, Omar 12 Johnson, Rikki 13 Lamphere, Troy 14 Myles, Jamathan 15 Cart 7 Proffit, Trevor 1 Robinson, Tyra 2 Shumaker, Jeff 3 Taylor, Carsen 4 Twombly, Richard 5 BEGIN IMMEDIATELY!!! 1. Go to Jefferson Labs pracbce SOLs 2. 8 th Grade Science 3. Select 40 QuesBons 4. E- MAIL TEST TO ME WHEN YOU FINISH AT 1. cellio`@glnd.k12.va.us Portaportal 1. Go to portaportal.com 2. Guest log- in: cesellio` 3. Go to website for simple machines and do acbvibes 4. Go to SOL pass.org science review Myles, KeShawwnna 6

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57 Seasons