What I Know Directions: Choose the letter of the correct answer. Click your answer. 1. What is the main cause of seismic waves? A. Earthquake B. Thunder C. Traffic D. Volcano 2. What type of wave is P wave? A. Electromagnetic B. Longitudinal C. Transverse D. Ultrasonic 3. Why is there an abrupt change in the speed of seismic waves as they travel inside the Earth? It is because seismic waves are ___________. A. colliding B. overtaking the compressional waves C. passing through a material with the same density D. going into a material with different properties and densities 4. Which of the following travels the fastest and is detected first in the seismic station? A. Love wave B. Surface wave C. Primary wave D. Secondary wave 5. Which kind of waves does NOT travel through a liquid? A. Love B. Primary C. Secondary D. Surface 6. What type of seismic waves are responsible for a destructive earthquake? A. Love B. Primary C. Secondary D. Surface 2 CO_Q2_Science 8_ Module 3
7. How do rock particles move during the passage of primary waves? A. no motion B. in circular motion C. back and forth parallel to the direction of the waves D. back and forth perpendicular to the direction of the waves 8. If P wave passes through solid to liquid media, what will happen to its velocity? A. increases B. decreases C. speeds up D. stays the same 9. What consist of a body wave? A. primary and Love waves B. surface and primary waves C. secondary and surface waves D. primary and secondary waves 10. What is the most destructive seismic wave? A. Primary B. Secondary C. Shear D. Surface 11. Which statement is correct? A. S waves are slower than P waves. B. P waves are slower than S waves. C. P waves have the same speed as the S waves. D. It is not possible to record the speed of S and P waves. 12. In which media can primary waves travel? A. both liquids and solids B. in liquids but not in solids C. in solids but not in liquids D. neither in solids nor in liquids 13. Which statement is true about P and S waves? A. P waves and S waves are the same. B. P waves are the slower waves that arrive second at the seismic station after S waves. C. P waves are the fastest waves that arrive first at the seismic station before S waves. D. P waves are the primary waves that move side to side as they travel from the earthquakes focus. 3 CO_Q2_Science 8_ Module 3
14. What type of seismic waves that can travel through crust? A. Body B. Primary C. Secondary D. Surface 15. Which of the following statements best describes the outer core? A. The outer core is thought to be liquid. B. P waves do not travel through the outer core. C. P waves and S waves can travel through the outer core. D. P waves travel through the outer core at a higher velocity than S waves. 4 CO_Q2_Science 8_ Module 3
Lesson 1 Seismic Waves You can see a light wave refracting from surfaces or reflecting from mirrors. You can also notice how a still water produces waves once dipped by a finger. This wave is a motion that propagates up and down or side to side and can be diverted by different media it travels. Waves are all around us, and the Earth produces waves as well. What are the different types of seismic waves that occur inside the Earth and how do they propagate? Do their propagation change as they pass through the different layers of the Earth? What are the implications of these behaviors in describing the interior of the Earth? Read the module and answer the activities to find out! What’s In Activity 1. Quake-events Directions: Rearrange the events in the order of their occurrence using the numbers 1 to 6. Type your answers inside the box. Events Order A. The rock underground suddenly breaks along a fault. B. Sudden release of energy causes the seismic waves that make the ground shake. C. When two blocks of rocks or two plates are rubbing against each other, they stick a little. D. The rocks are still pushing against each other but not moving. E. When rock breaks, earthquake occurs. F. The rock breaks because of pressure that builds up. 5 CO_Q2_Science 8_ Module 3
What’s More Activity 3. Getting into Puzzle iDirections: Complete the statements below. Drag your answers from the box and drop them on the appropriate blank. surface secondary P waves solid primary seismic wave S waves liquid 1. The ________________ wave is the fastest wave to travel. 2. The P waves can travel through _______________, liquids, and gases. 3. P waves are also known as ____________________ waves. 4. Secondary waves cannot travel through ___________________ and gases. 5. The ___________________ wave is the most destructive wave. 10 CO_Q2_Science 8_ Module 3
Activity 4. Let’s Talk About Waves A. Directions: Read the paragraph and complete the table below. Type your answer on the table. Seismic waves are also known as earthquake waves. There are two main types of earthquake waves: body waves and surface waves. The body waves have two types: primary waves (P waves) and secondary waves (S waves). Primary waves travel the fastest of all the waves. They are also unique in the aspect that they travel through all states Earthquake of matter - Wave solid, liquid, and gas. P waves are considered push-pull waves. They push and pull the rock as it moves through just like sound waves that push and pull the air. Secondary waves are not as fast as P waves. They cannot travel through liquids and gases. S waves travel in a side to side motions, like a piece of rope that you wiggle. Surface waves such as Love waves (L waves) are the slowest waves. They move along the Earth’s surface similar to the way the waves travel in the oceans, up and down. They are the most destructive waves because of the damages they create directly to the Earth’s surface. Comparison of Different Types of Seismic Waves Earthquake Medium Also known as Speed Motion Waves Travelled A. Body waves primary wave 1. 3. 5. push-pull secondary wave S waves 4. solids 7. B. Surface waves Love wave 2. slowest 6. 8. B. Directions: Write T if the statement is true and F if it is false. Type your answer on the blank. _________1. The primary wave is the slowest wave among the seismic waves. _________2. The secondary wave can travel through all states of matter. _________3. The most destructive wave is the surface wave. _________4. The primary wave is the first wave that can be detected. _________5. The two types of surface waves are the primary waves and Love waves. 11 CO_Q2_Science 8_ Module 3
Activity 6. Perfect Match A. Directions: Identify the types of seismic waves that travel inside the Earth. Type your answers inside the box. 1. 2. 3. Cross section of the Earth’s Interior Illustrated by: Kit Venzon B. Lagura Directions: Match Column A with Column B and Column B with Column C. Click to draw a line for connecting your answers. A B C Type of Wave Particle Motion Can travel through… A. transverse horizontal motion travel in 1. primary wave D. surface of the Earth only perpendicular to the direction of propagation B. alternating transverse motion perpendicular to 2. secondary wave E. crust only the direction of propagation C. alternating compression and dilation in the same 3. surface wave F. crust, mantle and core direction as the wave is propagating 13 CO_Q2_Science 8_ Module 3
What I Can Do Activity 7. Let’s Think First Directions: Below are possible situations during an earthquake. Choose and click the letter of the appropriate action. 1. If you are outside of your house, move away from the buildings. A I will do it. B I will just run anywhere. 2. If you are inside your house, get cover under a table. A I will do it. B I will not do it. 3. If you are in a moving car, what will you say to the driver? A Just keep driving. B Please stop. 4. Drop to the ground and protect your head. A I will do it. B I will not think about it. 5. Prepare a disaster emergency kit beforehand. A I will do it. B I will not do it. 15 CO_Q2_Science 8_ Module 3
Assessment Directions: Choose the letter of the correct answer. Click your answer. 1. What wave causes earthquake to occur? A. Electromagnetic B. Radio C. Seismic D. Sound 2. What does P in a P wave stand for? A. Parallel B. Partial C. Perpendicular D. Primary 3. What kind of seismic wave arrives last at seismic station? A. Love B. Primary C. Secondary D. Surface 4. Which type of wave vibrates parallel to the direction and travels in a push-pull motion? A. Love B. Primary C. Secondary D. Surface 5. Which of the following statements best describes primary wave? A. It travels through a vacuum. B. It causes rock particles to vibrate. C. It is the slowest, largest and causes the most destruction. D. It travels the fastest and causes rock material to move back and forth. 6. Which type of seismic wave moves rock particles up and down, or side-to- side perpendicular to the direction the waves are traveling in? A. Love B. Primary C. Secondary D. Surface 7. What type of seismic wave is S wave? A. Electromagnetic B. Longitudinal C. Transverse D. Ultrasonic 16 CO_Q2_Science 8_ Module 3
8. Which type of seismic waves can travel through crust, mantle, and core? A. Love B. Primary C. Secondary D. Surface 9. In which of the following media can secondary waves travel? A. gases only B. solids only C. liquids only D. solids, liquids and gases 10. Which of the following statements is NOT true about the secondary wave? A. S waves travel slower that P waves. B. S waves can travel through solid rocks. C. S waves move rock particles up and down. D. S waves can travel both in solid rocks and in liquid medium. 11. What kind of waves can travel through a liquid? A. Love B. Primary C. Secondary D. Surface 12. Which describes the motion of Love wave? A. circular motion B. push and pull C. side-to-side D. up and down 13. Which correctly describes Rayleigh waves? A. It can penetrate the outer and inner core. B. It rolls along the ground like a wave rolls along the ocean. C. It is faster than a Primary Wave. D. It is faster than an S wave but slower than P wave. 14. What is the velocity of a surface wave? A. 4 km/s B. 5 km/s C. 3 to 4 km/s D. 3 to 5 km/s 15. Why do S waves travel in solids only? A. Solids have enough shear strength. B. Solids have minerals and properties. C. Solids have particles closely packed together. D. Solids have rigid structure and resistant to the force applied. 17 CO_Q2_Science 8_ Module 3