What four things do we use to describe waves

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What four things do we use to describe waves?
Amplitude Frequency Wavelength Speed
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Waves
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Problem

• What is the frequency of red light if
• ? 656 nm?

4.57 x 1014 Hz
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Quantum

• A fixed amount
• Energy is emitted and absorbed in quanta

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Photon

• A quantum of electromagnetic energy

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Planck

• Discovered that as frequency increases, so does
  the energy of a wave.

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E h?

• E energy
• h 6.6262 x 10-34 Js h is Plancks constant
  J is unit of energy
• ? frequency

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Problem

• What is the energy in a wave of ? 6.00 x 1014
  Hz?

E 3.98 x 10-19 J
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Photoelectric Effect

• Phenomenon of electrons being removed from the
  surface of a metal when exposed to light.

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Photoelectric effect
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Dual nature of light

• Light behaves like waves
• Light behaves like individual particles.

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Line Spectrum

• Contains only certain wavelengths
• Each element has a unique line spectrum

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Bohr Atomic Model

• arranged electrons in fixed orbital shells around
  the nucleus
• electrons in each orbital have a fixed energy
  level.

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Quantum Number, n

• energy level of electron shells
• ground state (lowest inner level) n 1.

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Excited State

• electron receives photon of energy and moves out
  to a higher energy level.

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Review 1

• Are wavelength and frequency directly-related or
  inversely?

inversely
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Review 2

• Are energy and frequency directly-related or
  inversely?

directly