Please note that this presentation is slightly different to the one I use in class

1. Grade 8 Science Forces and Their Effects http://commons.wikimedia.org/wiki/File:Jal.747.newcolours.arp.750pix.jpg

2. The Solar System What keeps the planets moving? http://commons.wikimedia.org/wiki/File:Solar_sys.jpg

4. Forces are measured in Newtons, after Isaac Newton.

5. What force is required to: 1. open a drawer 2. untie a shoe lace 3. turn on a tap (difficult) 4. lift your pencil case. http://commons.wikimedia.org/wiki/File:Isaac-newton_1.jpg

7. Gravity pulls everything together.

8. We notice it as pulling us down towards the Earth.

9. Gravity also pulls the Earth towards the sun. http://www.icteachers.co.uk/children/sats/gravity.htm

11. Weight measures the force of gravity. It is measured in Newtons (N).

12. Short task: Measure the mass and weight force of four items in the laboratory. Item Mass (kg) Weight (N) Find something with a weight force of 1 Newton.

14. Weight (Newtons) = mass (kilograms) * 10

15. We MUST convert grams to kilograms first. 10 is the value of gravity on Earth.

16. Calculate the weight force of a 60kg person, an 800 kg car and a 50 gram feather.

18. In space, weight force is nearly zero.

19. Every place in the universe has its own number for gravity. 1. Calculate the weight force of a 60kg person on The Moon (1.7), Mercury (4), or Jupiter (2.6). 2. Explain why things weigh more on Jupiter. 3. What is wrong (scientifically speaking) with saying: “I weigh seventy kilograms.”

21. What is the weight of a 2kg object (on Earth)?

22. Calculate the weight of a 200g object (on Earth).

24. He developed a theory of motion (=???) which survived about 2000 years, until about 1600. Who disproved Aristotle's theories?

25. Stars (including planets) were fixed on large spheres, which moved in perfect circles around the Earth, and explained the movement of stars in the sky.

26. There were about 50 spheres moving in total. http://commons.wikimedia.org/wiki/File:Aristotle_Altemps_Inv8575.jpg

27. http://tutorsincalgary.com/science-tutor-calgary.jpg Please load the image shown at the URL below (it cannot be included in my presentation due to copyright).

29. Fire was the lightest, then air, then water, then earth.

30. Everything, if left alone, would move to its “natural state” and stop moving.

31. Iron was mostly Earth, whereas wood had some earth, some water and some air.

32. The Four Elements

33. What's in these? http://commons.wikimedia.org/wiki/File:Elliotts_car.jpg http://commons.wikimedia.org/wiki/File:Balloons-aj.svg http://commons.wikimedia.org/wiki/File:Air_.pollution_1.jpg

35. Violent motion is caused by living things applying a force to something. When the force stops, the motion stops. http://upload.wikimedia.org/wikipedia/commons/a/a2/Pushing_van_together.jpg

36. What Can't it Explain? http://godgrown.net/blog/2011/01/12/as-easy-as-the-arrows-job-in-archery/

39. Galileo Galilei is famous for being the first in recorded history to test whether heavier objects actually fall faster.

40. Conclusion: all objects fall at about the same speed. http://commons.wikimedia.org/wiki/File:Leaning_Tower_of_Pisa.jpg

42. They linked is law of Gravity with Kepler's Laws of planetary motion. http://commons.wikimedia.org/wiki/File:Newton_-_Principia_(1687),_title,_p._5,_color.jpg

44. Why do Cellphones Fly out Windows?

46. A force has a size (in N________) and a direction.

47. A force can be drawn as an arrow. The length of the arrow represents its size and the direction of the arrow represents the direction of the force.

48. A force can cause an object to change its speed (a_________), change its direction or change its shape.

49. Balanced Forces http://commons.wikimedia.org/wiki/File:Paperback-stack.png

50. Car (stationary) http://commons.wikimedia.org/wiki/File:Elliotts_car.jpg

51. Car (moving) http://commons.wikimedia.org/wiki/File:2009-03-11_Beat_up_car_driving_in_Durham.jpg

53. Note: the force of a fluid (eg water or air) pushing upwards on something (page 43 top left) is called a b_______________ force.

54. http://commons.wikimedia.org/wiki/File:Isarfloss.jpg

55. http://commons.wikimedia.org/wiki/File:Hot-air-balloon.jpg

56. The Cable Car http://en.wikipedia.org/wiki/Wellington_Cable_Car

57. http://en.wikipedia.org/wiki/Wellington_Cable_Car

58. http://en.wikipedia.org/wiki/File:Duquesne_incline.jpg

59. Hakone Ropeway http://commons.wikimedia.org/wiki/File:1_hakone_ropeway_2010.jpg

60. Water Balance Railway http://upload.wikimedia.org/wikipedia/commons/7/76/Funicular%2C_Centre_for_Alternative_Technology%2C_Machynlleth_-_geograph.org.uk_-_829550.jpg

63. Acceleration is a change in speed or a change in direction.

64. Force = mass * acceleration. http://commons.wikimedia.org/wiki/File:Elliotts_car.jpg

66. http://commons.wikimedia.org/wiki/File:Recreational_kayak.jpg http://commons.wikimedia.org/wiki/File:Model_rocket_launch_2_(Starwiz).jpg

70. Units are m/s (or cm/s, km/s etc).

71. Eg. Cliodhna is running during PE. After 20 seconds she has run 120. What is her speed? 1. Calculate how far Cliodhna would run in one minute (using the speed from the previous example).

72. 2.A. Moena is swimming at 2m/s. How long will it take her to swim a length of a swimming pool (25m)? B. How far can Moena swim during a 45 minute PE class if she swims for the whole class?

74. Measure the speed of a person walking and running. (It does not have to be the same person walking and running).

75. Use a distance of 5-10 metres.

76. Repeat each set at least twice, and take the average of all trials.

77. Present your results in a summary.

79. Apparatus: stopwatches, meter rulers

80. Prediction: ________ will walk at _____ m/s and _________ will sprint at _____ m/s.

81. Method: 1. Measure a suitable distance for someone to walk, and sprint. 2. Arrange a system for ensuring that the timing is accurate. 3. Record at least three trials, and calculate the average speed for walking and running.

83. __________Running Trial number Distance (m) Time (s) Speed (m/s) 1 2 3 Average speed Trial number Distance (m) Time (s) Speed (m/s) 1 2 3 Average speed

85. Equipment: tape measures, stopwatches

86. Work in group of 3, 4 or 5.

87. Safety:

88. No one is allowed on the road at any time (except crossing it at the proper crossing).

89. Signals should not distract cars. Write up a plan as a google doc for each group, and share it with me. It should include the names of each member of the group, and a detailed plan. It might help to have a table printed ready to go.

92. It is always in the opposite direction to motion.

93. Friction can occur between two surfaces. Air friction (drag) occurs when an object moves in the atmosphere (or another fluid). http://www.physics4kids.com/files/art/motion_friction1_240.jpg

94. Parachute What factors would determine how strong air resistance is? http://commons.wikimedia.org/wiki/File:Ronde_parachute.png

97. Acceleration is a constant change of speed. eg. Something starts at rest. After 5 seconds, it is travelling 10m/s. After 10 seconds, it is travelling 20m/s. How fast will it be travelling after 20 seconds? The acceleration of the object is __________.

100. Eventually the forces of friction and gravity are equal and opposite, so cancel each other out.

101. Newton's first law then applies, and the object keeps moving in the same speed and direction (downwards).

102. The fastest speed something can fall is called its terminal velocity.

103. Factors which affect terminal velocity:

104. Skydivers reach a terminal velocity of 190km/h (belly first) or 300km/h (head first). http://commons.wikimedia.org/wiki/File:Skydiver_on_back_of_partner_and_giving_thumbs_up.jpg

106. There is no need to use the particle theory for question 4 (but use it if you've learnt it!).

107. A hovercraft is shown below. http://en.wikipedia.org/wiki/Hovercraft

109. Introductory exercise: Consider the parachute we made last time. SKETCH a graph of its speed against time from the moment it is dropped to the moment it hits the ground. Assume there is minimal wind blowing. Time (seconds) s p e e d (m/s)

110. Time (seconds) S p e e d (m/s) 0 Parachute dropped 5 Parachute hits the ground The Falling Parachute The parachute took 5 seconds to reach the ground.

111. Time (seconds) s p e e d (m/s) 0 Parachute dropped 5 Parachute hits the ground The Falling Parachute

114. Time (seconds) 0 Parachute dropped 5 Parachute hits the ground The Falling Parachute The parachute fell 3.5 metres. d i s t a n c e (m) 3.5 0

117. an object's speed.

118. if and how its speed is changing (acceleration or deceleration).

119. A motion graph can show all of the above on the same graph.

121. A distance-time graph shows how far something has travelled on the Y axis.

122. Distance can not go backwards.

123. A speed-time graph shows how fast something is moving on the Y axis.

124. Bernie Walking at 1m/s 0 2 4 6 8 10 Time (seconds) Distance (m) 8 6 4 2 0 0 2 4 6 8 10 Time (seconds) Speed (m/s) 8 6 4 2 0

125. Sammie walking at 2 m/s 0 2 4 6 8 10 Time (seconds) Distance (m) 8 6 4 2 0 0 2 4 6 8 10 Time (seconds) Speed (m/s) 8 6 4 2 0

127. How would we describe Bernie's motion? 0 1 2 3 4 5 Time (seconds) 8 6 4 2 0 Speed (m/s) 8 6 4 2 0 Distance (m) 0 1 2 3 4 5 Time (seconds)

129. Work through Velocity-Time Graphs then Distance Time Graphs

130. Copy and complete the following table (without using what we did last time): Motion Speed-time Distance-time stationary Constant (non-zero speed) acceleration deceleration Note for the blog: 8C – we will do this slide next week (starting 19th)

132. Start from time = 0 when the train departs.

133. Tools: www.hyperdia.com

134. If you have a smartphone (and it's ok if you don't) install a GPS speedo and (as an extension) an accelerometer. Note for the blog: 8C – we will do this slide next week (starting 19th)

136. How long will it take to drive there? What do we need to know? What is 'Google's' average speed in km/h and m/s? Source: Google Maps

138. Estimate the instantaneous speed after 25 seconds. Time (seconds) Total distance covered (m) 0 0 10 50 20 150 30 250 40 350 50 500 60 600 70 650 80 690 90 700 100 700 Source: Google Maps

141. When working out how long it will take to get somewhere? Source: Google Maps

143. Use your spreadsheet to calculate the average speeds for each leg of the journey, and for the whole journey.

144. Hard: Sketch (either using a drawing tool on the graph, or by printing it, what the line on the graph might look like. Hint: think acceleration and deceleration: approximately how long does it stop for at each station?

145. Share your document with me.

146. Trains to Shibuya can reach speeds of over 100km/hr. Explain why your answers are so much lower than this. http://commons.wikimedia.org/wiki/File:Inside_of_Yokohama_Municipal_Subway_10000.jpg

148. Work through Velocity-Time Graphs then Distance Time Graphs

149. Copy and complete the following table to DESCRIBE (not draw) the motion in words. Motion Speed-time Distance-time stationary Constant (non-zero speed) acceleration deceleration

150. The Essay For this assessment task, you will need to research how Forces, Simple Machines and/or Magnetism has caused a particular problem in Japan or another country of your choice. It needs to be written as an essay and referenced using MLA format.For this assessment task, you will need to research how Forces, Simple Machines and/or Magnetism has caused a particular problem in Japan or another country of your choice. It needs to be written as an essay and referenced using MLA format.

152. If we read a random book, what do we need to say about the book so that someone else can find it?

153. Author, Title, Publication Info, Date Book Northedge, Andy. The Good Study Guide . 2nd ed. Milton Keynes: Open University, 2005. B ook with more than one author Cohen, Louis, Lawrence Manion, and Keith Morrison. Research Methods in Education . 6th ed. London: Routledge, 2007. Chapter in a book Dovey, Jon. "Reality TV" The Television Genre Book . Eds. Glen Creeber, Toby Miller & John Tulloch. London: British Film Institute, 2001.

154. Author, Title, Publication Info, Date Journal article Black, Sharon. "Harry Potter: A Magical Prescription for Just About Anyone." Journal of Adolescent and Adult Literacy 46.7 (2003): 4. Newspaper article Shepherd, Jessica. “Smoothie transition: is it really goodbye to the student union bar and hello to mango energisers and campus gyms?” The Guardian. 21 st August 2007: 6 Film Blair Witch Project. Dir. Daniel Myrick and Eduardo Sanchez. Artisan Entertainment , 1999 TV programme “ State of play.” Child Of Our Time. Victoria Bell. BBC. 2005

155. Author, Title, Publication Info, Date Web page Author, last name first. &quot;Webpage title.&quot; Website title . Date published/updated. Organization/publisher. Date accessed. < URL > Daimon, Sayuri. Tohuku. Students Share Tales of Disaster on Global Stage. The Japan Times Online. 22 September 2011. The Japan Times. 23 rd September 2011. http://search.japantimes.co.jp/cgi-bin/nn20110922f1.html Sometimes not all the information will be available; this does not matter. http://www.studygs.net/citation/mla.htm

157. Why does a pin prick but not a finger?

158. Why does a chair leave marks in the carpet? http://commons.wikimedia.org/wiki/File:Knife_01.JPG http://commons.wikimedia.org/wiki/File:Dwie_pinezki_(ubt).JPG http://www.inspectapedia.com/interiors/StainInterior040DJFs.jpg

161. One N/m 2 is called one Pascal, after the French genius Blaise Pascal.

163. Sample Problem 2 The square prism below has a length of 1m and a width and height of 20cm, and it has a mass of 2kg. Calculate the pressure in Pascals it exerts on the ground when: a) It is lying flat on its side as shown. b) It is standing tall.

169. Then continue with assignments.

171. Assume I walk at 3 m/s and run at 7 m/s. Source: Google Maps

173. As the temperature of the liquid or gas increases, the particles move faster, increasing the pressure.

174. Air and water pressure increases as depth increases, because the pressure needs to support more weight on top.

175. The air pressure at sea level is about 100 000 Pa. This means that a cubic metre could support a weight of __________kg if there were no air pressure from above.

176. Pressure in Fluids https://commons.wikimedia.org/wiki/File:Aquarium_empty.svg

178. Why doesn't it explode?

180. Would it be possible to suck water up a straw on the moon? http://www.one-school.net/Malaysia/UniversityandCollege/SPM/revisioncard/physics/forceandpressure/appatmosphericpressure.html

182. Explain why pressure around us is so high, but we cannot feel it.

183. Explain why it is not possible for humans to swim too deep.

184. Given that atmospheric pressure is about 100 000 Pa, show that a square meter could support 10000kg (about 15 cars).

185. Calculate the weight force on 1cm 2 of air at sea level, assuming the atmospheric pressure above.

187. Pressure = Force / Area.

188. Force =

189. The force is the same everywhere in a fluid.

190. A larger area makes a greater force.

191. Machines apply this principle to lift heavy objects. This is known as hydraulics. http://home.wxs.nl/~brink494/hydr_e.htm