Year 9 Science Semester 2 Practice Exam S2 GAU SOLUTIONS PDF

CRC NORTH KEILOR YEAR 9 SCIENCE PRACTICE EXAM SEMESTER 2, 2024 SECTION A: Multiple Choice Questions (50 Marks) Circle the correct response 1 Which layer of the Earth is made up of 2 What type of boundary occurs where two tectonic plates?...

CRC NORTH KEILOR YEAR 9 SCIENCE PRACTICE EXAM SEMESTER 2, 2024 SECTION A: Multiple Choice Questions (50 Marks) Circle the correct response 1 Which layer of the Earth is made up of 2 What type of boundary occurs where two tectonic plates? tectonic plates move toward each other? A. Core A. Transform Boundary B. Mantle B. Divergent boundary C. Crust C. Rift zone D. Inner Core D. Convergent boundary 3 What is the primary cause of tectonic plate 4 Which of the following is NOT a result of movement? tectonic plate movement? A. Earth’s magnetic field A. Earthquakes B. Convection currents in the mantle B. Volcanic eruptions C. Gravitational pull from the moon. C. Tsunamis D. Pressure from ocean tides D. Weather patterns 5 What name did Alfred Wegener give to his 6 With a divergent boundary to its south and a early theory, which laid the groundwork for convergent boundary to its north, in which plate tectonics? direction is the Australian plate moving? A. Magnetic striping A. West B. Continental drift B. East C. Oceanic rifting C. North D. Expanding Earth D. South 7 What does the Richter Scale measure 8 Which of the following tectonic settings does during an earthquake? NOT result in the formation of volcanoes? A. The magnitude of the earthquake A. Hotspots in the mantle B. The depth of the epicentre B. Convergent boundary where an oceanic and C. The frequency of seismic waves continental plate collide D. The occurrence of the earthquake C. Convergent boundary where two continental plates collide D. Divergent oceanic boundary 1 9 The diagram in Figure 1.1 shows the 10 Which of the following provides evidence that tectonic settings of the plate boundary on continents were once connected? the west coast of South America. What type of plate movement is shown at site A? A. Fossils of identical plant species found on continents separated by oceans B. Marine fossils found only along the coasts of A. Converging continents B. Diverging C. Dinosaur fossils found exclusively in tropical C. Transform regions D. None of the above D. Fossilized trees found in active volcanic regions 11 The process of seafloor spreading results in 12 The Juan Fernandez Islands, located 640 km the formation of what? from South America on the Nazca Plate, are moving eastward at 6 cm per year. In 1.5 million years, how much closer will they be to the coast? A. Oceanic Trenches B. Volcanic Hotspots C. Subduction zones A. 70km D. Mid-oceanic ridges B. 80km C. 90km D. 100km 2 13 In the context of magnetic striping, what 14 What is the primary cause of most earthquakes? does the term "reversal" mean? A. A shift in Earth's rotation A. Volcanic eruptions B. A change in magnetic orientation of B. Convection currents newly formed oceanic rock C. Movement of tectonic plates C. A fluctuation in ocean temperature D. Nuclear reactions in Earth’s core D. Separation of tectonic plate boundaries 15 Besides earthquakes and volcanic 16 What is the primary driver of volcanic activity at hotspots? eruptions, what other natural disaster is common in the Ring of Fire? A. Colliding tectonic plates A. Desertification B. Subduction of oceanic plates B. Tsunamis C. Seafloor spreading C. Tornadoes D. Upward movement of magma from hot D. Bushfires mantle plumes 17 What term is used for the point on 18 Why was Alfred Wegener’s theory of Earth's surface directly above the continental drift initially rejected by scientists? earthquake’s focus? A. He suggested Earth’s gravity moved A. Fault continents, which others found implausible. B. Dike B. Being a meteorologist, he lacked credibility in C. Epicenter geology. D. Rift C. There was no known mechanism that could move continents. D. Scientists couldn't visualize continents moving across the sea floor. 19 What is the rigid outer layer of Earth 20 What features are commonly found at called? transform boundaries where two plates slide past each other? A. Crust A. Chains of high mountains B. Mantle B. Mountain ranges with some volcanoes C. Asthenosphere C. Deep valleys with volcanoes D. Core D. Large faults and shallow, destructive earthquakes 3 21 What best describes the process of 22 Which type of crust, continental or oceanic, is subduction? older, and why? A. Formation of new oceanic crust at mid- A. Oceanic crust, because continental crust is ocean ridges destroyed at convergent boundaries B. Sinking of old oceanic crust into the B. Oceanic crust, because continental crust is mantle where it melts destroyed at divergent boundaries C. Sliding of tectonic plates past each other C. Continental crust, because oceanic crust is D. Formation of volcanoes above unusually destroyed at convergent boundaries hot parts of the mantle D. Continental crust, because oceanic crust is destroyed at divergent boundaries 23 Which layer of the Earth is responsible for 24 Which evidence supports the theory of seafloor spreading? generating the magnetic field? A. Earthquake activity concentrated only along A. Crust continental coasts B. Inner Core B. Increasing thickness of ocean sediment close C. Mantle to mid-ocean ridges D. Outer Core C. Matching patterns of magnetic stripes on either side of mid-ocean ridges D. High volcanic activity at transform plate boundaries 25 Which statement best explains why oceanic 26 The leaves of a green plant appear green because they: plates subduct beneath continental plates? A. Transmit green light and reflect all other A. Oceanic plates are thicker and less dense colours in the spectrum than continental plates B. Absorb green light and reflect all other B. Oceanic plates are thinner but denser colours in the spectrum than continental plates C. Reflect green light and absorb all other C. Continental plates are denser and colours in the spectrum therefore sink beneath oceanic plates D. Absorb green light and absorb all other D. Continental plates push oceanic plates colours in the spectrum upward, creating mountains 4 27 What is refraction? 28 Which colours of visible light have the shortest and longest wavelengths? A. The bending of light as it passes through A. Violet and yellow different substances B. Violet and blue B. The movement of light in a straight line C. Violet and red C. The process where light shines brighter D. Indigo and white as it travels D. Light scattering in random directions 29 The "normal" line in optics is an imaginary 30 What type of image does regular reflection produce? line that is drawn at what angle to a surface? A. Blurry and distorted images B. Clear, sharp images A. 45 degrees B. 180 degrees C. No images at all C. 90 degrees D. Images that are difficult to see D. 360 degrees 31 What happens to a ray of light when it 32 Which of the following substances slows down the speed of light the most? moves from air into water? A. Air A. It slows down B. Diamond B. It speeds up C. Perspex C. It remains at the same speed D. Water D. It is absorbed by the water 33 Visible light is part of which spectrum? 34 Fishermen often have difficulty accurately spotting fish underwater due to refraction. This happens because, as light exits the water and A. Electrotherapeutic spectrum enters the air: B. Hydrostatic spectrum A. It bends towards the normal because air has C. Electromagnetic spectrum a lower refractive index D. Emission spectrum B. It bends towards the normal because air has a higher refractive index C. It bends away from the normal because air has a higher refractive index D. It bends away from the normal because air has a lower refractive index 5 35 Total internal reflection is best described 36 Which statement is true about a blue pencil and a blue filter? as: A. A blue pencil absorbs blue light, and a blue A. Light being refracted so far away from filter absorbs blue light the normal that it reaches the boundary B. A blue pencil reflects blue light, and a blue between two transparent substances filter transmits blue light B. The angle of incidence being greater C. A blue pencil absorbs blue light, and a blue than the angle of refraction filter reflects blue light C. The angle of incidence being smaller D. A blue pencil reflects blue light, and a blue than the angle of refraction filter absorbs blue light D. Light being reflected so far towards the normal that it reaches the boundary between transparent substances 37 When parallel rays of light hit a convex 38 Light refracts when it: lens, what happens? A. Moves from a transparent object to an A. The light continues to travel in parallel opaque object lines B. Moves from one transparent object into B. The rays bend towards each other another transparent object C. Moves from a translucent object into a C. The rays bend away from each other transparent object D. The rays reflect back to the source D. Moves from an opaque object to a transparent object 39 When visible light passes through a 40 Which of the following materials will light NOT transparent prism, it is: pass through? A. An opaque brick A. Reflected B. A liquid or gas B. Redacted C. A vacuum C. Dispersed D. A transparent solid D. Dissolved 41 The reversal of your image in a plane 42 Which of the following is a non-luminous object? mirror is called: A. The Sun A. Bilateral reversal B. Laptop screen B. Lateral inversion C. The Moon C. Lateral reversal D. A fire D. Bilateral inversion 6 43 Why does a red object appear red? 44 When light enters a glass block from the air, what happens? A. It reflects red light and absorbs orange, yellow, green, blue, indigo, and violet light A. It slows down and bends away from the B. It absorbs red light and reflects orange, normal yellow, green, blue, indigo, and violet light B. It slows down and bends towards the normal C. It absorbs all colours but absorbs red the C. It speeds up and bends away from the most normal D. It reflects all colours, but red is reflected the D. It speeds up and bends towards the normal most 45 Which three colours of light mix to make 46 What colour will an object appear when white light passes through a blue filter and then a white light? green filter? A. Yellow, green, red A. Blue B. Cyan, yellow, magenta B. Green C. Green, blue, red C. Cyan D. Red, green, orange D. White 47 The speed of light is 300,000 km/s. How 48 Which colour absorbs the most wavelengths of long does it take for light from the Sun to visible light? reach Earth? A. White A. Eight seconds B. Violet B. Eight minutes C. Cyan C. Eight hours D. Black D. Eight years 49 Which of the following objects is 50 Which statement best describes the law of reflection? translucent? A. The angle of incidence is always greater than A. A frosted glass bottle the angle of reflection. B. A piece of cardboard B. The angle of incidence is always equal to the C. A solid metal spoon angle of refraction. D. A clear plastic sheet C. The angle of incidence is always equal to the angle of reflection. D. The angle of reflection is always 90° to the surface. END OF MULTIPLE CHOICE 7 SECTION B: Short Answer Questions (35 Marks) 1. Why are converging boundaries are also known as destructive boundaries? Converging boundaries are also known as destructive boundaries because when two tectonic plates move toward each other, one plate is often forced down into the mantle and eventually melts. This process destroys parts of the Earth's crust, which is why it's called a "destructive" boundary. 1 Mark Referring to the map below as evidence, explain in detail why South America experiences large numbers of destructive earthquakes and volcanoes? South America experiences frequent earthquakes and volcanic activity because of its location near a convergent plate boundary. Plate Boundaries: South America lies along a boundary where the oceanic Nazca Plate collides with and is forced under the continental South American Plate. This type of boundary is called a subduction zone. Subduction Zones: At subduction zones, one plate is pushed beneath another, building up pressure between the plates. When this pressure releases, it triggers strong earthquakes. The subducting plate also melts as it sinks, creating magma that rises to the surface and leads to volcanic eruptions. Frequent Tectonic Activity: Regions located along these convergent plate boundaries, like South America, experience regular seismic and volcanic activity due to the ongoing movement and interaction of the tectonic plates. 2 Marks 8 2. Draw a cross-section of an earthquake, and identify and label the epicenter and the focus. 2 Marks 3. Describe the movement at each of the following plate tectonic boundaries. For each type, list the natural disasters commonly associated with it. You may include a diagram to support your answer if needed. a. Transform: At a transform boundary, two tectonic plates slide past each other horizontally. This sideways motion can cause intense friction as the plates grind along each other. Natural Disasters: Earthquakes are commonly associated with transform boundaries due to the buildup and sudden release of stress as the plates move. b. Convergent: At a convergent boundary, two tectonic plates move toward each other. When an oceanic plate meets a continental plate, the oceanic plate is usually subducted (forced down) beneath the continental plate. When two continental plates collide, they push upwards, forming mountain ranges. Natural Disasters: Earthquakes, volcanic eruptions, and mountain-building are common. Subduction zones often generate powerful earthquakes and volcanoes, while continental collisions can cause intense earthquakes. c. Divergent: At a divergent boundary, two tectonic plates move away from each other. This movement creates space that is often filled by rising magma, which cools to form new crust. Natural Disasters: Volcanic activity and smaller earthquakes are common along divergent boundaries, especially along mid-ocean ridges where new ocean floor is created. 3 Marks 9 4. Calculate the value of 𝒙𝒙 in each of the diagrams below. 40° a. 𝒙𝒙 = 40° (Angle of Incidence = Angle of Reflection) 164° b. 𝒙𝒙 = 8° Straight Line Mirror = 180°- 164° = 16° ÷ 2 so 𝑥𝑥 = 8° 2 Marks 5. Three beams of light are directed through a concave lens. Draw the path the light will take as it passes through the lens, and clearly mark the focal point on your diagram. 10  If the concave lens were replaced with a thinner lens, like the one below, how would the position of the focal point change? Illustrate the new path the light rays would take with the thinner lens. 3 Marks 1. Thick Convex Lens: o Light rays entering the lens converge towards a point, the focal point. Because the lens is thick, the rays will bend sharply. o The focal point (F) for a thick lens is closer to the lens. 2. Thin Convex Lens: o In a thin lens, the light rays converge more gradually, so they meet at a focal point further away from the lens. o The focal point (F) for a thin lens is farther from the lens compared to the thick lens. Here is a diagram showing the path of light through both a thick and a thin convex lens: Thick Convex Lens: The light rays bend sharply, converging at a focal point closer to the lens. Thin Convex Lens: The light rays bend less sharply, with a focal point farther from the lens. The focal points are marked in red (labeled "F") in each diagram. 11  6. Green light is projected onto the Italian flag (shown below) in an otherwise completely dark room. State what colour the green, white, and red sections would appear? In a completely dark room, with only green light projected onto the Italian flag: Green section: The green section of the flag would appear green because it reflects green light. White section: The white section would also appear green, as white reflects all colors of light, including green. Red section: The red section would appear dark or black, as red absorbs green light and does not reflect it. So, in green light, the Italian flag would look green in both the green and white sections, and black in the red section. 3 Marks 7. Explain why a tsunami is more likely to occur at a subduction zone than at a transform fault boundary. A tsunami is more likely to occur at a subduction zone than at a transform fault boundary because of how the plates move: 1. Subduction Zones: At subduction zones, one plate is pushed under another. This causes the ocean floor to suddenly move up or down, displacing a large amount of water and creating a tsunami. 2. Transform Fault Boundaries: At transform faults, the plates slide past each other horizontally. This movement doesn’t cause the ocean floor to shift up or down, so it doesn't create a tsunami. 1 Mark So, subduction zones can cause vertical movement that displaces water, leading to tsunamis, while transform faults only cause horizontal movement, which doesn't. 8. The table below shows the speed of light in both glass and water. Explain how the change in the speed of light affects the amount of refraction of light within in the medium Medium Speed of Light (km/s) Glass 185,000 Water 110,000 When light passes from one medium to another, its speed changes, causing it to refract. The amount and direction of refraction depend on the refractive index of the medium. Refractive index is a measure of how much a medium slows light. A higher 1 Mark refractive index means light slows down more and bends more. 12  In glass, the speed of light is 185,000 km/s, slower than in air. As light enters glass, it slows down, causing it to bend towards the normal (the imaginary line perpendicular to the surface). This is because the refractive index of glass is higher than air, and light slows down when it enters the glass. In water, the speed of light is 110,000 km/s, even slower than in glass. Light entering water will slow down even more, so it bends even more, again towards the normal. Since water has a higher refractive index than glass, light bends more in water than in glass. In summary, when light enters a medium where it slows down (with a higher refractive index), it bends towards the normal. Light bends more in water than in glass because the refractive index of water is higher, causing it to slow down more and bend more towards the normal. 9. The image below shows a city in Mexico. Painting buildings white keeps them cooler in the hot Mexican summer than they would be otherwise. Explain why painting buildings white helps keep to them cool in hot climates? Painting buildings white helps keep them cool in hot climates because of how light and heat are reflected and absorbed. Reflection of sunlight: White paint reflects most of the sunlight that hits the building, including the sun’s heat. This means less energy is absorbed by the building, keeping it cooler. Absorption of heat: Dark colors, on the other hand, absorb more sunlight and heat, making the building warmer. 1 Mark In summary, white paint reflects sunlight, reducing heat absorption and helping to keep buildings cooler in hot climates. 10. Explain how beams of sunlight passing through raindrops can create a rainbow. In your answer, be sure to include the terms refraction, refract, dispersion, and disperse. Also, explain which colour of light bends the most and why. Sunlight creates a rainbow when it passes through raindrops due to refraction and dispersion. 1. Refraction: Light refracts or bends as it enters the raindrop because it slows down in water. 2. Dispersion: Different colours of light bend by different amounts. Red light bends the least, while violet light bends the most. 3. Reflection: After refracting inside the raindrop, light reflects off the back and exits, spreading out into a rainbow. 13 The result is a rainbow, with red on the outer edge and violet on the inner edge because red bends the least and violet bends the most. 3 Marks 11. What are the three primary colours in science? And why are these colours referred to as primary colours? The three primary colours in science are red, blue, and green. They are called primary colours because they cannot be made by mixing other colours, and can be combined to create other colours 2 Marks 12. a. Explain how the following two diagrams contain evidence in favour of Plate Tectonic Theory. Light brown shading/red= area of increased earthquake activity The Ring of Fire supports Plate Tectonic Theory because it is an area with high tectonic activity along plate boundaries, particularly around the edges of the Pacific Plate. 1. Volcanic Activity: The Ring of Fire is home to many active volcanoes that form as tectonic plates collide and subduct (one plate moves under another), causing magma to rise and create volcanoes. This pattern of volcanic activity aligns with plate boundary locations, supporting the theory of plate interactions. 2. Earthquakes: The region experiences frequent and intense earthquakes due to the movement and collision of plates. Earthquakes along these boundaries 14  provide further evidence of the shifting, interacting plates that Plate Tectonic Theory describes. 3. Mountain and Trench Formation: The Ring of Fire also contains deep ocean trenches and mountain ranges formed by converging plates, which Plate Tectonic Theory predicts. In summary, the volcanic activity, earthquakes, and geological formations around 2+2=4 the Ring of Fire align with Plate Tectonic Theory, showing where plates meet and Marks interact. Magnetic striping on the ocean floor provides strong evidence for Plate Tectonic Theory: 1. Magnetic Reversals: As molten rock rises at mid-ocean ridges and cools, magnetic minerals within it align with Earth’s magnetic field. Over time, Earth’s magnetic field reverses, so new rock records the opposite magnetic alignment. This creates a pattern of magnetic stripes on either side of the ridge. 2. Symmetry: The magnetic stripes are symmetrical on both sides of mid-ocean ridges, showing that new crust is continuously formed at the ridge and pushed outward as plates move apart. 3. Age of the Crust: The age of the ocean floor increases with distance from the ridge, supporting the idea of seafloor spreading, where plates move away from each other. These magnetic patterns confirm that plates are moving and creating new crust, as predicted by Plate Tectonic Theory. 15 13. You have set up a light kit to shine a single ray onto the side of a plain mirror. On this diagram, locate the normal, the incident ray, the angle of incidence, the reflected ray and the angle of reflection. 4 Marks 16  14. What happens at a convergent boundary where an oceanic plate meets a continental plate, and how is it different from when two continental plates meet? At a convergent boundary between an oceanic and a continental plate, the denser oceanic plate subducts under the continental plate, creating trenches, volcanoes, and earthquakes. When two continental plates collide, neither subducts. Instead, the crust folds and rises, forming mountain ranges with strong earthquakes but little volcanic activity. So, oceanic-continental convergence leads to subduction and volcanoes, while continental-continental convergence builds mountains. 2 Marks 15. What is dispersion of light, and how does it create a rainbow? Dispersion of light is the process where white light separates into its different colours when it passes through a medium, like a raindrop or a prism. This happens because each colour in the light bends, or refracts, by a different amount due to its wavelength. Red light bends the least, and violet light bends the most. As sunlight enters and exits a raindrop, this dispersion spreads the colours out, creating a rainbow with red on the outer edge and violet on the inner edge. 1 Mark END OF SHORT ANSWER QUESTIONS /35 Marks 17 SECTION C: Extended Response (15 Marks) You are investigating how different colours of light pass through various types of glass. You have three pieces of glass with different colours: a. Clear glass b. Red-tinted glass c. Blue-tinted glass Each piece of glass is tested by shining a white light through it, and the amount of light that passes through (measured in lux) is recorded. The experiment is conducted under identical conditions for all glass pieces. NOTE: A lux is a unit of measurement for illuminance, which refers to the amount of light that falls on a surface. One lux is equal to one lumen per square meter. It measures how much light is received by a surface, such as a piece of glass or a room. The higher the lux value, the brighter the light. 1. Write an aim for the experiment: To investigate how different colours of glass 1 Mark (clear, red-tinted, and blue-tinted) affect the amount of light that passes through when exposed to white light. 2. Make a full list of materials you will need: White light source (e.g., LED lamp) Light meter (to measure light in lux) Clear glass piece Red-tinted glass piece Blue-tinted glass piece Dark, controlled environment (to eliminate outside light) Stand or holder for glass pieces Data recording sheet or notebook 2 Marks Ruler (optional, to ensure consistent distance between light source and glass) Timer (optional, if measuring light over a set time) 3. List three controlled variables and explain how they will be controlled: Controlled Variables: 1. Distance between the light source and the glass: The distance should be kept the same for each piece of glass to ensure consistent light intensity. This can be controlled by placing the light source and glass at fixed distances using a ruler. 2. Environmental lighting: The experiment should be conducted in a dark room or controlled environment to eliminate interference from external light sources. This ensures that the only light passing through the glass is from the white light source. 3. Intensity of the white light: The light source should be kept at a constant intensity for all tests. This can be controlled by using the same type of light 3 Marks source and ensuring it is turned on at the same setting for each glass piece. 18  4. What is the dependent variable that is being measured in this scenario: The dependent variable being measured is the amount of light (in lux) that passes 1 Mark through each piece of glass. 5. The results were as follows: Type of Glass Type of Glass Light Passing Through (Lux) Clear Glass Clear glass 180 Red-Tinted Glass Red-tinted glass 120 Blue-Tinted Glass Blue-tinted glass 100 Graph this data in a scatter plot on the graph below, ensuring you add appropriate axis labels and values. 5 Marks 19  6. Given these results, write an appropriate conclusion to the experiment In conclusion, the data demonstrates that the type of glass significantly impacts the amount of light transmitted through it. Clear glass allows the most light to pass through, with a lux value of 180. Both the red-tinted and blue-tinted glasses reduce the amount of light, with blue-tinted glass allowing the least (100 lux) and red-tinted glass transmitting slightly more (120 lux). These findings suggest that tinted glasses filter light to varying degrees, with the blue tint being the most effective at reducing light transmission. 3 Marks END OF SECTION C: EXTENDED RESPONSE /15 Marks END OF PRACTICE EXAM 20