6.6.1.3 Reflection of Waves

Question 1

How can waves be reflected?

Answer 1

• at the boundary between two different materials

Question 2

What can happen to a wave at the boundary between two different materials?

Answer 2

• absorbed
• transmitted

Question 3

What happens when a wave is reflected?

Answer 3

• only reflect off a flat surface
• smoother the surface means stronger reflected wave
• rough surfaces scatter light in all directions so it won’t reflect wave
• angle of incidence = angle of reflection

Question 4

Why is light reflected and not absorbed by the material if the object is opaque?

Answer 4

• electrons absorb light energy
• reemit it as a reflected wave

Question 5

What happens when a wave is transmitted?

Answer 5

• waves pass through a transparent material
• more transparent, more light will pass through
• can still refract but process of passing through material and emerging is transmission

Question 6

What happens when a wave is absorbed?

Answer 6

• if frequency of light matches energy levels of electrons, light will be absorbed and not reemitted
• reemitted over time as heat
• if a material appears green, only green light has been reflected and the rest of frequencies in visible light have been absorbed