Presentation on theme: "What is a wave? A disturbance that travels through space or matter, with a transfer of energy. There are two types of waves. 1. Mechanical Waves 2. Electromagnetic."— Presentation transcript:
What is a wave? A disturbance that travels through space or matter, with a transfer of energy. There are two types of waves. 1. Mechanical Waves 2. Electromagnetic Waves
What is a Mechanical Waves? A mechanical wave requires a medium to travel through. Their movement can be longitudinal or transverse Transverse Waves The motion of the medium is perpendicular to the motion of the wave Up and Down Waves Example: ocean wave, waves on a rope, standing wave, Longitudinal Waves (or compression wave) The motion of the medium is parallel to the motion of the wave Back and Forth Waves Example: sound wave
Parts of a Longitudinal Wave Compression When waves are close together Rarefaction When waves are far apart
Compare the transverse and longitudinal wave. http://www.acoustics.sal ford.ac.uk/schools/lesso n1/flash/slinky.swf http://www.acoustics.sal ford.ac.uk/schools/lesso n1/flash/slinky.swf
Types of Mechanical Waves: How can you tell them apart? All mechanical waves are not the same For example, ocean waves are a different type of wave from sound waves Although they both transfer energy through a medium, the movement of the wave through the medium is very different This motion of the medium compared to the movement of the wave can be classified as either TRANSVERSE OR LONGITUDINAL
What is an electromagnetic wave? Electromagnetic waves DO NOT need a medium to travel. An EM wave moves is a transverse wave even though it doesn’t use a medium to transfer energy. Can you think of some examples? Which wave does this picture represent?
Parts of an Electromagnetic Wave moving as a Transverse Wave Crest- highest point on a wave Amplitude- height of a wave (also the volume of the wave) Trough- lowest point on a wave Wavelength- The distance from one wave top, or crest, to the next. Frequency-is the number of complete cycles in one second.
Diagram of a Transverse Wave* CREST TROUGH WAVELENGTH AMPLITUDE
Look at the frequency http://www.acoustics.salford.ac.uk/schools/lesson1/fla sh/freq.swf http://www.acoustics.salford.ac.uk/schools/lesson1/fla sh/freq.swf
Draw a line to divide your paper in half. Use string to create a transverse wave and label the parts using your PowerPoint notes.
Use your PowerPoint on waves to create and label a longitudinal wave.