1. How does life depend on water? 2. Give three examples of the interactions between spheres. International School of Arts and Sciences ISAS

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1 Grade 6 Science Summer Work International School of Arts and Sciences ISAS Earth s spheres Our planet has many parts. These parts work together. Without these parts, our spinning days would be over. The Earth's parts are called systems. A system is a group of independent parts that work together as a whole. The Earth has four major systems or spheres. These systems are the geosphere, the hydrosphere, the atmosphere, and the biosphere. The biosphere is the system where we belong. The prefix bio- means "life." It includes all of the people, animals, plants, and other organisms on our planet. The plants and trees in the biosphere give us the oxygen we need to survive. They provide the food humans and animals need to survive. The animals also are a source of food for humans. Every organism in the biosphere needs each other. The geosphere is the part of Earth way below our feet. It is the crust and mantle. The crust is the outer layer of the Earth. We stand on the top of the crust. The mantle is the layer beneath the crust. The inside of the Earth is very hot. Scientists learn a lot about our planet's insides from earthquakes and volcanoes. When volcanoes erupt, they send lava or liquid rock to the surface. There is also heat and pressure inside the Earth. This heat and pressure cause our mountains to form. Our hydrosphere includes all of the water on our planet. The oceans, rivers, lakes, streams, and ponds are part of the hydrosphere. Even the glaciers or large blocks of ice on Earth have water. We depend on the Earth's water for food and power. We not only use fresh water for drinking, but we also use the animals in the sea for food. Water is used to help make power. Some of our electricity is made from the power of water. 1. How does life depend on water? 2. Give three examples of the interactions between spheres. 1 P a g e

2 1. How are energy and matter exchanged among the four main components of the Earth system? 2 P a g e

3 1. Label the graph below. 2. Fill in each blanks with the correct word. The is the thickest layer of the earth. The temperature of the earth gets as you go down to the and gets as you move toward the. The densest layer of the earth is the. Landforms are found above the. 3. Explain which spheres are interacting when a volcano erupts. 3 P a g e

4 What is sound? Sound is made with vibrations. Whenever an object vibrates it causes air particles to move and bump into each other in wave-like motions. We call these vibrations sound waves. Just like water ripples when you throw a stone into it, sound waves ripple and keep going until they run out of energy. Our ears vibrate in a similar way to the original source of the sound. This is how we hear many different sounds. 4 P a g e

5 Describe the frequencies you see in each. What kind of sound do you think they are making? Figure 1 Figure 2 Figure 1: Figure 2: 5 P a g e

6 Have you ever tried to make a pretty tone by rubbing the rim of a glass? When you wet your finger and drag it around the rim, it slips and sticks to the glass similar to the way a violin bow slips and sticks to the strings that it plays. This slip-stick motion causes the glass to start vibrating. Try adding more water to the glass. What happens to the tone? Do you think there is a sound in space? Why or why not? Explain your answer. 6 P a g e

7 Experiment with Sound Waves Every time a sound is produced it emits a sound wave. You can picture the shape of sound as a wave on the ocean: the sound starts at one end of the wave and spreads out. By the time the wave reaches the shore you can hear it. For a home example of this phenomenon, take a rubber band and spread it tightly between your fingers. Now strum the rubber band. The movement of the band creates vibration, or sound waves. This experiment will demonstrate how sound travels, using nothing more than a spoon and a string. What You Need: Metal spoon 30 inches of kite string (40 inches for an adult) What You Do: 1. Tie the handle of the spoon at the midpoint of the string. 2. Wrap the ends of the string around your index fingers (pointer fingers). 3. Place your fingers in your ears. 4. Lean over so that spoon hangs freely and swing the spoon so it taps against a door. 5. Hit the door again, this time harder. 7 P a g e

8 Questions What did you hear? Was it a soft sound like a bell, and then a louder sound like a church bell? The sound came because the spoon vibrated, causing sound waves to travel up the string and into your ears. The loudness or quietness of the sound depends on the amplitude (height of the wave). 8 P a g e

9 The Speed of Sound on a String Objective: This classic children s game will demonstrate sound's ability to travel through air vs. through a piece of string. Research Questions: When you talk to a friend, your voices travel from your mouths through the air (a gas) to each other's ears. What happens when you connect your mouths and ears with a piece of string (a solid)? Materials: Two paper or plastic cups (small yogurt containers are durable) Scissors String Masking tape A friend Experimental Procedure: 1. Using the point of the scissors, poke a hole in the middle of the bottom of each cup. 2. Stand a few feet away from a friend and talk to each other in normal (not yelling) voices. 3. Keep moving apart until you can no longer hear each other. 4. Hold one of the cups up to your mouth and speak into it while your friend listens into the other. 9 P a g e

10 Now can you hear each other? 5. Next cut a length of string long enough to stretch the distance between you and your friend when you could no longer hear each other. 6. Poke the ends of the string through the holes in the bottoms of the cups (poke it upwards through the bottom) and tape the ends securely to these bottoms. 7. Hold onto one cup, have your friend hold onto the other, and walk away until the string is taut (pulled straight, not sagging). 8. Talk into one cup while your friend holds the other cup over her ear. (Remember to keep the string taut.) Switch. Now can you hear each other through the cups? (Remember to move the cups from your mouths to your ears and back depending on if you re listening or speaking.) Why do you think attaching the cups with the string allows you to hear each other? 9. More fun with this project: Try it with longer and longer pieces of string. How far apart can you get and still have the phone work? Try different widths/types of string. What happens if you use different sizes, shapes, materials of cups? What if someone grabs onto the string while you re talkin 10 P a g e

11 Make Your Own Electricity Sometimes, a large number of atoms in an object will gain or lose electrons (negatively charged subatomic particles that are found at varying distances from an atom's nucleus). When this happens, the entire object takes on an electric charge. The term static electricity describes situations where objects carry electric charge. And by using static electricity generated from her body, a child can cause a small fluorescent lamp bulb to light up! What You Need: Plastic comb Small fluorescent lamp What You Do: 1. Tell your friend to rub a comb through her hair. The friction between her hair and the comb will cause electrons to "jump" from her hair to the comb. 2. If your friend then touches the comb to the end of a fluorescent light bulb, the charged comb will discharge into the light bulb causing the bulb to emit small pulses of light. This action will generate a great deal of excitement especially if conducted in a darkened room. What Happened? More than likely your friend will want to know why this happens. Tell her that static electricity occurs, for example, when she rubs a balloon on her shirt (you might wish to actually try this). The friction between the cloth and the balloon causes negatively charged particles (electrons) to transfer from her shirt to the balloon. The shirt then has an overall positive charge because it has more protons than electrons. The balloon takes on a negative charge because it has extra negative charges (electrons). The balloon will then stick to the shirt or to another surface, such as a wall. 11 P a g e

12 Static electricity has many uses in homes, businesses, and industries. For example, the copying machines found in most offices are electrostatic copiers. They make duplicates of pictures or written documents by attracting negatively charged particles of toner (powdered ink) to positively charged paper. 12 P a g e

13 Series and Parallel Circuits It used to be that if you had a string of holiday lights and one bulb went out, the whole string no longer worked. This was because the lights were set up in a series circuit. Recently, companies have started producing lights and other electronics that are set up in parallel circuits. Circuits carry electric current when they are in a closed loop, and can act differently depending on the physical set up of the circuit. Current, which is the flow of electrons in a circuit, can be carried through wires, barriers, and any functional pieces of circuits, like lights. In a series circuit, the parts of the circuit are in a row, one after the other so current flows through them. Parallel circuits are set up so that the current has an independent path to take through each piece. For holiday lights, this means one bulb can burn out and not affect the rest of the circuit. Problem: Are bulbs in a parallel or series circuit brighter? 13 P a g e

14 Materials 9V battery Tape Aluminum foil 2 identical flashlight bulbs Procedure 1. Tape an 8-inch strip of aluminum foil to the positive terminal of the 9V battery. Make sure the aluminum foil is touching the metal. 2. Tape another 8-inch strip of aluminum foil to the negative terminal of the 9V battery. 3. Wrap the end of the aluminum strip attached to the positive terminal around the light bulb s metal screw cap. 4. Take a 4 -inch strip of aluminum foil and wrap one end around the second light bulb. 5. Place the bottom of the light bulb attached to the positive terminal on the loose end of the other battery s foil strip. 6. Place the bottom of the second light bulb on the foil strip attached to the negative terminal. 7. You have created a series circuit. Take note of how brightly the bulbs shine. 8. Now, let s create a parallel circuit. First, remove the light bulbs from the system. 9. Take two 4 -inch strips of aluminum foil and fold one of each of the ends around the strip coming off the positive terminal of the battery. It should look like the rungs of a ladder, but only connected on one side. 10. Wrap the loose ends of the 4 -inch strips around the metal screw cap of each light bulb. 11. Place the bottom of each of the light bulbs against the foil strip attached to the negative terminal. 12. Record your observations, comparing the brightness of the two circuits you created. 14 P a g e

15 Results The bulbs in parallel circuit will be brighter than the bulbs in series circuit. Why? In parallel circuits, each independent path experiences the same volt age drop. For series circuits, the voltage drop is split between the components (lights, for example) depending on their resistances. Bigger voltage drops draw a larger current, which means more electrons flow through the bulb, making it brighter. 15 P a g e

16 A wave is a disturbance that carries energy through matter or space. It has two parts: a) The first part is higher than the part behind it. The higher part is called the crest. b) The low part is called the trough. -A complete wave is made up of one crest and one trough. -A wavelength is the distance from the middle of the crest of one wave to the middle of the next crest. -The amplitude is the distance from the resting position to either the top of the crest or the bottom of the trough. -Pitch is how high or low a sound is. 16 P a g e

17 If the pitch is high, the frequency is high. If the pitch is low, the frequency is low. -Frequency is the number of times a string vibrates in a given amount of time. -Loudness is how loud or soft a sound is. Decibels are used to measure the sound level. If the amplitude of the wave is high, the sound is loud. If the amplitude of the wave is low, the sound is soft. -Light waves can travel through space but sound waves travel through matter only. -The electromagnetic spectrum is made from electric and magnetic fields. -The part of the spectrum that you can see is called visible light. 1) Define the following: a) Wave b) Frequency 17 P a g e

18 c) Pitch d) Amplitude e) Wavelength 2) Examine the figure below and answer with true or false. a) The point H is in the middle of the crest: b) The point C is in the middle of the crest: c) The segment EF represents a wavelength: d) The segment CD represents the amplitude: e) The segment CJ represents two wavelengths: f) The segment DG represents one complete wave: Design a Great Glass Xylophone! This amusing activity incorporates music into an educational science experiment! Your child will love learning about sound waves as he makes and plays sweet-sounding melodies on his very own glass xylophone. He ll delight in exploring the effect of varying amounts of water in each glass, and will get to make up some enchanting tunes at the same time! 18 P a g e

19 What You Need: a) 6 tall glass glasses, bottles, or jars (preferably the same shape and size) b) Water c) Food coloring or colorful soft drink mix d) Metal spoon, wooden spoon, or wooden popsicle sticks e) Jug What You Do: 1. Line up the bottles or glasses in a row. 2. Tap gently on each of the glasses. What sort of sound is created? Do the glasses all make the same sound? 3. Put the water in the jug and mix in the food coloring or drink mix. 4. Carefully pour the water into the glasses, making sure there is a different level of water in each glass. 5. Tap the glasses again. What sort of noise do they make now? Do all of the glasses make the same sound now? 6. Vary the tones by changing the amounts of water. Record your observations. 7. Invite your friend to play a tune! Adjust the musical notes that are created by adding more or less water to each glass. What 's Going On? When your friend taps the glasses, he generates sound waves that travel through the water. When there is water in the glasses, the sound waves are altered as they need to travel through water. The more water is present in a glass, the lower the sound note. 19 P a g e

20 Variation: If you are using bottles for this activity, blow into the bottle and to listen to the sound produced. Are they the same or different from the sound he gets when he taps the bottles? You might be surprised, as the result is the opposite. The more water there is in the bottle, the higher the note. This is because the sound waves created when the bottle is blown travel through the air rather than the water. The less water present in the bottle, the more air there is! 20 P a g e

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