1. INTRODUCTION TO WAVES Mrs. Gergel 2014/2015

2. The Nature of Waves Imagine that your family has just returned home from a day at the beach. You had fun playing in the ocean under a hot sun. You put some cold pizza in the microwave for dinner, and you turn on the radio. Just then, the phone rings. It’s your friend calling to ask about homework. In the events described above, how many different waves were present?

3. Brainpop! http://www.brainpop.com/science/energy/waves/

4. What are waves? A wave is any disturbance that transmits energy through matter or empty space. Waves are created by a series of vibrations. There are two main classifications of waves. Mechanical Waves and Electromagnetic Waves. Waves only transmit energy, not matter.

5. Mechanical Waves Mechanical waves are waves that require a medium to transmit energy. A medium is the material through which a wave travels Examples: air, water, dirt Examples of mechanical waves are ocean waves, seismic waves, sound waves, and slinky waves.

6. Electromagnetic Waves Electromagnetic waves Do Not require a medium to travel. This means that they can travel in a vacuum (like space). Examples of electromagnetic waves are rainbows, radio waves, and X-Rays.

7. Types of Waves There are three main types of waves. Transverse Waves Longitudinal (compression) Waves Surface Waves (a mix of both)

8. Transverse Waves Transverse waves move perpendicular to the direction of the wave. This means they move up and down.

9. Longitudinal Waves Longitudinal waves move parallel to the direction of the wave. This means they move back and forth.

10. Surface (Combination) Waves Surface waves are also known as combination waves. This is because they occur on Earth’s surface when generated from an earthquake and are also seen traveling along the surface of an ocean. They are a mix between longitudinal and transverse waves. With a surface wave, the particles of the medium travel in a circular motion compared to the direction of energy transfer.

11. Activity Use the Slinkies provided to create a longitudinal wave. How do you know this is a longitudinal wave? Use the Slinkies to create a transverse wave. How do you know this is a transverse wave? Use the tip of your pencil to touch the water in the pie tin. What type of wave have you created? How do you know?

12. Exit Quiz