Science 7 final exam study guide 13. Define atmosphere (p90): a thin layer of air that forms a protective covering around the planet 14. List the mixture of gases in Earth’s atmosphere: Nitrogen % = 78 Oxygen % = 21 Other gases % = 1 15. Draw the diagram of the layers of the Earth’s atmosphere (p92). Exosphere = cold = outer space thermosphere = warm = mesosphere = cold = stratosphere = warm OZONE LAYER troposphere = cold = the air we breathe 16. Where is air pressure greater (p94)? Ground level (troposphere) , molecules are condensed 17. Does temperature increases or decrease with altitude in the mesosphere (p95)? decrease 18. Define ozone layer and explain why it is important to earth (p96). SKIP 19. What is CFC’s? SKIP 20. Why does the Equator receive more direct sunlight than the poles (p103)? Earth’s tilt is on its axis. The solar energy is spread over a large area starting from the south pole to the equator. 23. warm air is ___ dense than cool air (p107). less 24. Differences in ___ and pressure cause air movement and wind (p107). Density Define (back page) radiation= transfer of energy (E) in the form of rays conduction= transfer of E that occurs when molecules bump each other convection= transfer of heat by the flow of a heated material condensation= change from gas to liquid evaporation= change from liquid to gas precipitation= droplets combine and falls out of cloud. CIRRUS = feathery clouds associated with fair weather STRATUS = puffy white clouds clouds may cause deforestation three different height categories for clouds 28. Define weather (p118): the interaction between air, water and sun causes weather 29. How does air temperature cause wind (p119)? Wind is caused by air moving from areas of high pressure (cool, dense air) to areas of low pressure (warm, rising air). 31. Describe how clouds form (p122). Draw a picture. Formed by water droplets suspended in air. 32. What are the four main types of precipitation (p124)? R Sleet = raindrops pass through a layer of freezing air Snow = when the air temperature is below freezing Hail = can break windows and destroy crops 33. Define air mass (p126). A large body of air that is similar to the Earth’s surface. 34. What kind of air mass would you expect coming out of the following areas: Gulf of Mexico= maritime and tropical central Canada= polar and continental Pacific Northwest (off Pacific Ocean)= polar and maritime Mexico= continental and tropical MARITIME = moist air over water CONTINENTAL = dry air over land POLAR = cold air TROPICAL = warm air Define, draw and label 4 types of fronts = p127 to 128 cold front = when cold air advances toward warm air, [draw blue triangles] warm front = when warm air advances over heavier cold air, [draw red semi-circles] occluded front = cold air forces warm air upward, [draw purple semi-circles and triangles on the same line] stationary front = neither cold nor warm air advances, [draw red semi-circles alternating with blue triangles] Describe the following (p131 to 133) thunderstorm = heavy rainfalls, lightning, thunder occurs in warm, moist air mass. Most powerful storm. hurricane = travels east to west. tornado = violent, rotating column of air on the ground blizzard = the winds are 56 km/h, low temp, and snow for 3 hrs warning= when severe weather conditions already exist skip 37, 38, 39 Part 3: forces & motion define (p684-689) = equation displacement is the distance and direction between starting and ending positions = no equation speed = distance (m)/ time (s) velocity = displacement (m)/ time (s) acceleration = (final speed – initial speed)/ t m /s2 Solve 41. Mr. Mayo takes 15 seconds to run the 100 meter dash. What is his average speed? Time= 15 s speed= distance/time distance= 100 m ? =100m/15s speed= ? 6.6 m/s 42. Ms. Jen travels 800 km to visit a friend and travels at an average speed of 40 km/hr. How long does her trip take? Distance = 800 km speed= distance/time speed= 40km/hr time=? 43. Mr. Zetlin goes from a speed of 0 m/s to 10 m/s on his skateboard in 5 seconds. What is his acceleration? Time = 5 s a= (final spd - init spd)/t initial speed = 0 m/s a= (10-0m/s)/ 5s final speed = 10 m/s a= 2m/s2 acceleration=? Newton’s Three Laws of Motion (p690-705) 1st Law of Motion = an object at rest stays at rest with a constant speed and in a straight line 2nd Law of Motion = for every action there is an opposite and equal reaction 45. What is inertia (p692)? The more mass an object has, the more resistance it has, to change the motion. 46. The more ___ an object has, the more inertia is has (p692). mass 47. A force is a ___ or a ___ (p693). Push , pull 48. A ___ force is a force exerted when two objects are touching each other (p693). contact 49. ___ and ___ forces are examples of long range forces. Gravity, electrical 50. ___ forces will cause a change in motion (p693). unbalanced 51. Write the formula for acceleration according to Newton’s 2nd Law of Motion (p694). Force (Newton) = mass (kg) X acceleration (m/s2) Rearrange the formula to use for finding F (p695). a= F/mass, mass= Force/a 52. What is the force of Mr. Mayo’s 60kg toy truck when it has an acceleration of 4 m/s2? A= 4m/s2 force = mXa mass= 60kg force= ? 53. Ms. Jen moves a 25kg rock out of her way while climbing. The rock has a acceleration of 3 m/s2 , what is the force she used to move the rock? 54. Define gravitational force (p696): it is the pull of an object towards the center of the Earth definition = an amount of matter in an object = mass plus gravity unit = kg = Newton change w gravity = no = yes instrument to measure = triple beam balance = spring scale 55. What is friction …(p697-699)? Force that opposes motion, causes heat and slows down an object 56. Why is it necessary for tires to have grooves or tread in them? 57. Why do you feel the Earth’s gravitational force, but not the gravitational force of someone sitting next to you? The more mass, the greater gravity. The closer the distance, the greater the gravity 58. Carbon dioxide ___ as we use more from fossil fuels and global ___ (p730). increases, warming 59. Earth can be ___ by the greenhouse effect however ___ gas increases the greenhouse effect (p163). warmed, carbon dioxide 60. Define fog (p123). Air condenses to the ground. 61. Define smog = it is a type of pollution that combines smoke and ___. fog 62. The four inner planets are __ (p195). Mercury, Venus, Earth, and Mars 63. Mercury is the ___ planet to the Sun (p196). closest 64. Venus is called our sister planet because it looks like the planet ___ (p196). Earth 65. Mars has the largest ___ in our solar system (p196). volcanoes 66. A meteor is a ___ that enters Earth’s atmosphere (p196). Meteoroid 67. Comets are made of ___(p200). rocks and icy particles 68. Asteroids are ___ that are located between planets ___ (p200). Rocks, Mars and Jupiter 68. Define solstice (p182). The sun’s rays are north and south of the equator. 69. Define equinox (p183). The length of day equals the length of night. 70. The equator receives ___ of the sun’s rays. The Earth’s ___ does not change much (p183). most, temperature 71. The north and south pole has the ___ amount of sun’s rays during the solstices (p182). least 72. If the sun is above the equator, which season is the north pole? This also gives the north pole during this season 24 hrs of sunlight (p183). summer 73. The three land features of the moon are ___ (p184). craters, maria, and highlands 74. Define lunar eclipse (p190). When the moon is in the Earth’s shadow. 75. Earth is a ___ shape (p179) with a ___ shadow (p180). spherical, curved 76. Earth ___ 24 hrs in a day (p180). rotates 77. Define AU (p194). An Astronomical Unit; it is the distance between Earth and the Sun 78. Define biotic. living or once living biotic examples: tiger, leather shoes, wooden ruler, cotton 79. Define abiotic. non living abiotic examples: plastic ruler, ceramic mug 80. Energy is neither created or destroyed but recycled 81. The water cycle has no beginning or ending 82. Opposable thumb can grab and reach for things. 83. Hominids = first humanlike primates 84. earliest hominids are Australopithecus 85. humans are called homo sapiens sapiens