Physical Science Chapter 15 Waves Section 1

Physical Science Chapter 15 Waves A disturbance that transits (carries) ENERGY through matter or space.

Physical Science Chapter 15 Waves Most waves travel through a medium. A medium is some kind of physical environment (matter) through which the waves travel.

Physical Science Chapter 15 Waves Mechanical Waves The types of waves that require matter to transmit energy through are called mechanical waves.

Physical Science Chapter 15 Waves If a wave moves through MATTER, the matter moves back and forth or up and down, but the matter does NOT move with the energy.

Physical Science Chapter 15 Waves Electromagnetic Waves Waves caused by a disturbance in electric and magnetic fields. Do NOT require matter (a medium) to transmit energy through. Also referred to as “light waves”.

Physical Science Chapter 15 Waves Electromagnetic Waves As you will learn later, moving electric charges create magnetic fields and moving create electric current.

Physical Science Chapter 15 Waves Mini-Quiz #1 1). What is the definition of a wave? 2). What is the primary difference between mechanical waves and electromagnetic waves?

Physical Science Chapter 15 Waves Team Mini-Quiz #1 1). What is the definition of a wave? A disturbance that transits ENERGY through matter or space. 2). What is the primary difference between mechanical waves and electromagnetic waves? Mechanical waves need a medium to travel through.

Physical Science Chapter 15 Waves Team Mini-Quiz #1 3). What are the SEVEN types of EMR? Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays. 4). What are the seven colors of visible light? red, orange, yellow, green, blue, indigo and violet.

Physical Science Chapter 15 Waves A disturbance that transfers ENERGY through matter or space. But WHAT causes the “disturbance” that creates the wave?

Physical Science Chapter 15 Waves Vibrations Vibrate: to move back and forth (usually rapidly and with a steady rhythm).

Physical Science Chapter 15 Waves Vibrations Involve transfers of energy To create vibrations in a slinky, you have to move it sideways or up-and-down You transfer energy to the slinky

Physical Science Chapter 15 Waves Vibrations: Mechanical Waves Mechanical waves are created by a vibrating (moving) object.

Physical Science Chapter 15 Waves Vibrations: Electromagnetic Waves Electromagnetic waves are created by vibrating charged particles.

Physical Science Chapter 15 Waves Transverse Wave A type of wave that causes particles in the medium to move perpendicular (up-and-down) to the direction of the wave (energy movement)

Physical Science Chapter 15 Waves Transverse Wave Crest- highest point Trough- lowest

Physical Science Chapter 15 Waves Transverse Wave Wavelength- a complete cycle Amplitude- distance up to a crest or down to a trough

Physical Science Chapter 15 Waves Longitudinal (Compressional) Wave A type of wave that causes particles in the medium to move in the same direction (parallel to the movement or back-and-forth) as the direction of the wave (energy movement).

Physical Science Chapter 15 Waves Longitudinal (Compressional) Wave Compression- region where the medium is pushed together Rarefaction- region where the medium is spread out.

Physical Science Chapter 15 Waves Longitudinal (Compressional) Wave Wavelength-distance from compression to compression.

Physical Science Chapter 15 Waves Surface Waves Combines the motions of transverse waves and longitudinal waves, so the medium moves in a circular motion.

Physical Science Chapter 15 Waves Surface Waves Surface waves occur at the boundary between two different mediums. Water and air (ocean waves) Ground and air (earthquake waves)

Physical Science Chapter 15 Waves Surface Waves Water waves Medium particles move in a circle; they do not move with the energy (Fig. 9p. 513)

Physical Science Chapter 15 Waves Surface Waves Water waves The circles get smaller as the water gets deeper.

Physical Science Chapter 15 Waves Seismic Waves Waves traveling through the Earth (or other body) caused by earthquakes, explosions, etc. There are two types, P and S types.

Physical Science Chapter 15 Waves Seismic Waves (Body Waves) P (primary waves) are longitudinal S (secondary) waves are transverse.

Seismic Waves Two main types of seismic waves: Body waves travel through Earth’s interior Primary waves (P-waves) Secondary waves (S-waves) Surface waves travel on Earth’s surface Rayleigh waves Love waves CPS5e, Section 21.1 Figure 21.3

Physical Science Chapter 15 Waves Surface Waves Tsunamis- Giant surface waves

2). Draw a transverse wave; label the two parts of the wave? Mini-Quiz #2 1). What causes most waves? 2). Draw a transverse wave; label the two parts of the wave? 3).Draw a longitudinal wave; label the two parts of the wave. 4). What is different about the direction of movement of the medium in transverse and longitudinal waves? 5).Describe the motion of a surface wave & give an example.

Physical Science Chapter 15 Waves Team Mini-Quiz #2 1). What causes most waves? Vibrations 2). Draw a transverse wave crests and troughs

Physical Science Chapter 15 Waves Team Mini-Quiz #2 3).Draw a longitudinal wave compressions rarefactions

Physical Science Chapter 15 Waves Team Mini-Quiz #2 4). What is different about the medium movement in transverse and longitudinal waves? In transverse waves the medium moves at 90 degrees to the direction of wave movement (“up-and-down”). In compressional waves the medium moves in the same plane as the direction of wave movement (‘back-and-forth.”)

Physical Science Chapter 15 Waves Team Mini-Quiz #2 5).Describe the motion of a surface wave & give an example. The medium in surface waves moves forward and back and up and down, creating circular movement. An example is a water wave.