1. GHSGT Review Day 2 – Describe the Properties of a Wave

2. What is a wave?

3. Echos and Reflections Sound waves that are reflected can cause an echo. Mirrors can reflect light waves to give us reflected images.

4. Properties of a wave Wavelength – the length of a wave from peak to peak Frequency – the number of wave peaks that occur in a unit of time (measured in hertz, Hz)

5. As the wavelength increases the frequency decreases.

6. What do you know about light?

7. Electromagnetic spectrum – made up of visible and invisible waves of transverse energy waves, ranging from low frequency to very high frequency, which can travel at the speed of light in a vacuum.

8. Light waves are part of the electromagnetic spectrum. The frequency of a light wave determines its color.

9. Why is a sunset more red?

10. We could use mirrors to manipulate light waves… A flat mirror is a smooth shiny surface that reflects light. Light travels in a straight line as it is reflected from a surface. –The incident ray is the light ray that strikes the surface. –The reflection ray is the light ray that reflects off the surface. –The Law of Reflection states that the angle of reflection equals the angle of incidence.

11. REFLECTION Bouncing a ray or wave off a surface

12. REFRACTION is the bending of a wave or light by the change in density of the medium

13. Using lenses to bend light Images in convex Images in concave mirrors are always mirrors are always smaller. bigger.

14. Just a few more terms to review… Interference - the superposition of two or more waves resulting in a new wave pattern superpositionwaves Diffraction - the bending and spreading of waves when they meet an obstruction.waves

15. Special things to know about sound… cannot travel through empty space or a vacuum. Sound travels faster through solids than through liquids or gases. When temperature increases, the speed of sound increases. When the air becomes more humid, the speed of sound increases.