1. WAVES

2. Mechanical Energy is transferred when objects are pushed or pulled over a distance.
The amount of energy transferred increases as the strength of the force increases or as the distance covered by the object increases.

3. MORE FORCE = MORE ENERGY TRANSFER
MORE STRENGTH = MORE ENERGY TRANSFER
GREATER THE DISTANCE = MORE ENERGY TRANSFER

4. When energy is transferred waves are created.
A wave is a disturbance caused by energy transfer
Almost all waves need a substance to travel through.

5. A ______________ is the material a wave travels through.
Examples: air, water, some solids
Waves that require a medium are called mechanical waves
Waves travel the fastest in which type of medium?
Liquid, solid gas?
WHY?

6. Types of Mechanical Waves
1. Transverse Waves: a wave that vibrates the medium at right angles (perpendicular) to the direction the wave is traveling.

7. The high point on a transverse wave is called the _______________.
The low point on a transverse wave is called the ___________________.

8. 2. Longitudinal Waves: a wave that vibrates the medium in the same direction in which the wave is traveling
These waves compress and expand.

9. Compression: this is the area where the coils are close together.
Rarefaction: this is the area where the coils are spread out.

10. 3. Surface Waves: these waves are a combination of transverse and longitudinal waves.
These waves travel along a surface that separates two mediums.
Examples: ocean waves and seismic waves

11. Frequency
Wave period – the time needed for one wave to pass a certain point.
Frequency – is the number of waves that pass a certain point in a specific amount of time. (usually 1 sec.)
Frequency is measured in HERTZ (Hz)

12. Frequency vs Wavelength
Speed = distance/time
Wave speed = wavelength/wave period
The longer the wavelength the lower the frequency
The shorter the wavelength the higher the frequency