Transfer of Energy Waves and Circuits Energy: the ability to do work Wave: a disturbance that transfers energy from place to place

WAVES (transfer energy) Mechanical Waves (must have a medium to travel through) Transverse Waves (medium moves at a right angle to direction of wave) Longitudinal Waves (medium moves parallel to direction of wave)

Types of Waves Transverse Wave a wave that moves the medium at right angles (perpendicular) to the direction in which the wave is traveling

Transverse Waves Crest: the highest part of a transverse wave Trough: the lowest part of a transverse wave

Motion in a Transverse Wave What are the crest, trough, and rest position?

Types of Waves Longitudinal Wave a wave that moves the medium in the same direction (parallel) to the direction in which the wave is traveling

Longitudinal Waves Compression: the part of a longitudinal wave where the medium is pushed together Rarefaction: the part of a longitudinal wave where the medium is spread apart

Motion in a Longitudinal Wave Which are the areas of compression and rarefaction in the diagram ?

All waves (transverse and longitudinal) have the same properties: Wavelength Amplitude Wave speed Frequency

Properties of Waves Wavelength the distance between two corresponding parts of a wave (such as the distance from crest to crest or trough to trough)

Properties of Waves Amplitude the maximum distance that the particles of the medium carrying the wave move away from their rest positions. The greater the amplitude, the greater the energy in a wave.

Properties of Waves Wave Speed how far the wave travels in a given length of time Examples: A tsunami wave travels through the ocean at approximately 600 mph. Sound waves travel through the air at 768 mph.

Properties of Waves Frequency the number of waves that pass a certain point in a given amount of time; measured in Hertz (Hz) – 1 Hz is one wave per second

What are the properties of a wave? What are the parts of the wave?

Properties of Waves All waves have amplitude, wavelength, frequency, and speed. Wavelength TRANSVERSE WAVE Crest Rest position Trough Direction of wave LONGITUDINAL WAVE Compression Amplitude Rarefaction Wavelength

Electric Circuits

Electric Current – the continuous flow of electrons through a material Conductor – a material through which electrical charge can easily flow (metals such as silver, gold, copper, aluminum, and iron) Insulator – a material through which electrical charge cannot easily flow (rubber, glass, plastic, and wood)

ELECTRIC CIRCUITS a complete, unbroken path through which an electric current can flow

A symbol in a circuit diagram represents a part of the circuit. Circuit Diagrams Scientists use circuit diagrams to represent a circuit. Battery Wire Device such as a light bulb Switch

ComponentCircuit SymbolFunction of Component WireTo pass current very easily from one part of a circuit to another Battery Supplies electrical energy. The larger terminal (on the left) is positive (+), and the smaller terminal (on the right) is negative (-). Lamp (lighting) Symbol is used for a lamp that provides illumination, for example a car headlamp or light bulb. Switch (On) Allows current to flow only when it is in the closed (on) position. Switch (Off) Will not allow current to flow when it is in the open (off) position.

SERIES CIRCUIT All parts of the circuit are connected one after another along one path; in a series circuit there is only one path for the current to take The number of bulbs in a series circuit affects each bulb’s brightness.

The different parts of the circuit are on separate branches; in a parallel circuit, there are several paths for the current to take PARALLEL CIRCUIT

How Does an Electrical Circuit Work? Use the key to fill in the blank label boxes. DIAGRAM PRACTICE

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