Waves

DO NOW: How many waves can you identify in this passage? List them. You have just returned home from a day at the beach. You are hungry from playing in the ocean under the hot sun. You microwave some left over pizza. The phone rings, and you turn on the radio.

SWBAT Students will be able to identify different forms of waves and describe how waves transfer energy.

ANALYZE INFORMATIVE TEXT a) Read over the QUESTIONS: What is a WAVE? What is a medium? How do waves transfer energy? b) Read the passage. Place a box around the bold-faced vocabulary terms . Underline important key concepts that answer the questions listed above. Answer the questions.

What is a wave? A wave is a disturbance that transmits energy through matter or space. A medium is a substance or material which carries the wave.

What is the difference between a mechanical wave and an electromagnetic wave?

Energetic Waves Activity Tie a rope to the back of your chair. Hold the other end so that it is almost straight but not tight. Move the rope up and down quickly to create a single wave. Record your observations onto your worksheet. Which direction does the wave move? Compare the movement of the rope with the movement of the wave. Where does the energy come from?

Put a piece of tape on the rope What direction does the tape move? Is it in the same direction as the wave? Record your answer. Energy can be carried from its source by a wave. But the material does not move with the energy. Ex leaf on water, sound in air. Which direction does the wave move? Compare the movement of the tape with the movement of the rope with the movement of the wave. Where does the energy come from?

Reflection What are different forms of waves? How do waves transfer energy?

DO NOW Remember our class discussion yesterday on waves? Write a short paragraph involving different forms of waves that occur in everyday life.

SWBAT Students will be able to identify how Transverse waves move and identify their highest and lowest points. (Day 1- Transverse waves) Today’s Agenda: Do Now Analyze Informative Text Activity Reflection

Analyze Informative Text Two Kinds of Waves **Transverse Waves (p.7)- Day 1 Read the passage: Types of Waves. Place a box around the bold-faced vocabulary terms. Underline how both longitudinal and transverse waves move.

What are Transverse Waves? Transverse waves are waves in which particles vibrate with up and down motion. The term “transverse” means MOVING ACROSS.

How do Transverse Waves move? They Vibrate perpendicular (at right angles) to the wave travel.

Transverse Waves An example of transverse waves are Electromagnetic waves.

CRESTS vs. TROUGHS Crests- highest points of a wave Troughs – lowest points of a wave

Transverse Waves Activity Use your Slinky to demonstrate a transverse wave: Work with a partner One of you move your end of the Slinky back and forth (left and right, like a snake crawling), perpendicular to its stretched length. The other student must hold his or her end of the Slinky still A series of transverse waves will be generated and will travel through a medium (Slinky)

DO NOW Yesterday, we used a slinky to represent how transverse waves move. a) Describe how transverse waves move. b) Draw an example of a transverse wave and label crests and troughs.

SWBAT Students will be able to compare and contrast transverse and longitudinal waves.

Analyze Informative Text Two Kinds of Waves **Longitudinal Waves (p.8)- Day 2 Read the passage: Types of Waves. Place a box around the bold-faced vocabulary terms. Underline how both longitudinal and transverse waves move.

How do Longitudinal Waves Move? Longitudinal Waves vibrate parallel (in the same direction of) to wave travel. (The “LONG” way)

Longitudinal Waves For example: sound waves The other end of the medium moves without the actual movement of matter.

How Do Longitudinal Waves Move? How can you create a longitudinal wave? You can create a longitudinal wave on a spring.

Longitudinal Waves How do Longitudinal Waves Move? The other end of the medium moves without the actual movement of matter. Longitudinal Waves How do Longitudinal Waves Move?

COMPRESSION: a section on a longitudinal wave where particles are crowded together.

RAREFACTION: A section where the particles are less crowded than normal.

Longitudinal Waves Activity COMPRESSION Use your Slinky to demonstrate a longitudinal wave: Work with a partner Stretch it out along the table One of you grasp and draw several coils of a stretched Slinky toward yourself Release the coils The other student must hold his or her end of the Slinky still A longitudinal wave pulse will be generated and travel down the length of the Slinky.

Longitudinal Waves Are composed of Compressions, where the parts of the medium (coils of the Slinky) are closer together than normal In this investigation, you created (generated) compressional longitudinal waves The waves traveled through a medium (the slinky).

Longitudinal Waves Activity RAREFACTION Use your Slinky to demonstrate a longitudinal wave: Work with a partner Stretch it out along the table One of you stretch a segment of the Slinky Release the coils The other student must hold his or her end of the Slinky still A longitudinal wave pulse will be generated and travel down the length of the Slinky.

Longitudinal Are composed of Rarefactions, where the parts of the medium are farther apart than normal In this demonstration, you created (generated) rarefactional longitudinal waves The waves traveled through a media (the slinky)

Complete your Venn diagram comparing transverse waves and longitudinal waves.

DO NOW: Describe how ocean waves move DO NOW: Describe how ocean waves move. Indicate if water waves are transverse or longitudinal, or a combination of both. Explain.

Ocean Waves A combination of longitudinal & transverse

SWBAT Students will be able to compare and contrast transverse and longitudinal. (Review session for quiz tomorrow.) Today’s Agenda: Do Now Analyze Text (Nature of Waves/ Guided Note sheet) Venn Diagram Class Activity Class Discussion Reflection

Analyze Informative Text Two Kinds of Waves *Transverse and Longitudinal Waves Read the passage: Types of Waves. Read over your highlighted work from yesterday. Compare your guided notes to your reading passage.

TURN AND TALK Let’s Review Complete your Venn diagram comparing transverse waves and longitudinal waves.

Slinky Activity Using the slinky, create a transverse wave. Explain how you created this transverse wave. Make sure to include the terms crests and troughs in your explanation. b) Using the slinky, create a longitudinal wave. Explain how you created this longitudinal wave. Make sure to include the terms compressions and rarefactions in your explanation.

Reflection

DO NOW A. B. Observe the waves below. Identify the type of wave it is. Explain. A. B.

SWBAT Students will be able to explain of how two forms of waves move and identify their similarities and differences. Today’s Agenda: Do Now Review Venn Diagram Quiz Reflection

What Should I Do After The QUIZ Today? Hand in your quiz. 2)Read the passage: Properties of Waves. 3a) Highlight the reading. 3b) Define on loose leaf: Amplitude, Wavelength, Frequency, crest, trough, compression, rarefaction

DO NOW Observe the wave below. 1) What type of wave is this. Explain DO NOW Observe the wave below. 1) What type of wave is this? Explain. 2) What is the difference between compression and rarefaction?

Students will be able to compare and contrast the parts of a wave. SWBAT Students will be able to compare and contrast the parts of a wave. Today’s Agenda: Do Now Analyze Informative Text Guided Note-Taking Activity Reflection

Analyze Informative Text Read the passage: Properties of Waves (p.10-12) Place a box around the bold-faced terms and underline important key concepts defining those terms.

Parts of a Wave

WAVELENGTH the distance between two waves In transverse waves – distance between two crests or troughs 2. In longitudinal waves – distance between two compressions or rarefactions

Amplitude Amplitude -wave height (the distance from the middle of a transverse wave to the crest or trough)

FREQUENCY Frequency – the number of waves that pass a point in one second Long wavelengths have low frequencies Short wavelengths have high frequencies

Look at the parts of a wave.

Parts of a Wave Wavelength – In transverse waves – distance between two crests or troughs In longitudinal waves – distance between two compressions or rarefactions Frequency – the number of waves that pass a point in one second Long wavelengths have low frequencies Short wavelengths have high frequencies Amplitude (wave height) – the distance from the middle of a transverse wave to the crest or trough

Activity: Change Amplitude Hold a slinky on the floor between you and your partner. Move one end from side to side at a constant rate. The number of times you move it from side to side is (back and forth) each second is the frequency. Keeping the frequency the same, increase the amplitude. How did the change in amplitude affect the wavelength? Record your observations.

Activity- Change Frequency Now shake the slinky back and forth twice as fast (double the frequency). What happened to the wavelength? Record your observations.

REFLECTION Summary Write 3 sentences showing how each property changes the other: use the terms frequency, amplitude and wavelength.

Electromagnetic Waves Are waves which are capable of transmitting its energy through a vacuum (i.e., empty space) Produced by the vibration of electrons within atoms on the Sun's surface Travel through space until they reach Earth Examples are light and heat Are transverse waves which mean the particles vibrate ACROSS the direction of the wave

Mechanical Waves Are not capable of transmitting their energy through a vacuum (space) Require a medium in order to transport their energy from one location to another Sound waves are mechanical longitudinal.

Mechanical Waves Waves traveling through a solid medium can be either transverse waves or longitudinal waves.

Do Now How are light and sound alike? How are they different? Use your Nature of Waves packet to help you. On 2 pages (p 4) of your packet, make a gigantic Venn diagram comparing the two. Light Sound