1. The Basics

2. Simple Harmonic Motion A body will undergo SIMPLE HARMONIC MOTION when the force that tries to restore the object to its rest position is proportional to the displacement of the object. A pendulum and a mass on a spring both undergo this type of motion which can be described by a SINE WAVE Simple harmonic motion is one of the most common types of motion found in nature.

3. Common Examples Ripples in a pond A swing Radio Waves

4. What is a wave? A disturbance traveling through a medium. Energy is passed without permanently disturbing the medium. The Source of Waves For the wave to propagate (travel), something must vibrate. This vibration is the source of the wave.

5. Types of Waves Mechanical Waves Transmit energy without transmitting matter Water waves, sound waves, waves on a rope Electromagnetic Waves Light waves, radio waves, X rays No medium is needed to transmit energy Travel at the speed of light = 300,000,000 m/s Matter Waves Electrons and small particles show wave-like behavior

6. How does the Medium effect Waves? The medium is the material being disturbed. Disturbances move through a medium at specific speeds (wave speed). Wave Speed is characteristic of the medium only. Waves travel faster in stiffer mediums.

7. Amplitude Amplitude is a measure of the strength of the wave distance from midpoint to crest or trough

8. Wavelength distance between one crest and the next is the symbol for wavelength

9. Frequency and Period Frequency is the number of vibrations per second measured in hertz Period is the time to make one complete cycle frequency = 1 / period period = 1 / frequency

10. Wave Speed The distance between crests is divided by the time between the crests wave speed = frequency x wavelength v = f

11. Wave Speed Wave speed depends on the nature of the medium When a wave goes from one medium to another there may be a change in the wave direction changes speed changes

12. Transverse Waves Sine wave motion of wave at right angles to movement of wave Has an obvious up- down or side-to-side vibration

13. Longitudinal Wave particles move back and forth in direction of the movement of the wave

14. Basic Types of Waves Transverse Waves Longitudinal (compression)Waves