I. Waves and Particles De Broglie’s Hypothesis Particles have wave characteristics Waves have particle characteristics λ = h/mn where λ is the wave length. “h” is the Plank’s constant = 6.626 x 10-34 J.s m = mass Wave-Particle Duality of Nature Waves properties are significant at small momentum

Visible Light is a type of electromagnetic radiation-a form of energy that exhibits wavelike behavior as it travels through space. Examples: microwaves that cook our food. X-Ray, radio waves.

WAVE LENGTH Wave Length is represented by the Greek letter lambda, λ, is the shortest distance between equivalent points on a continuous wave. It is usually expressed in meters, centimeters or nanometers (1nm = 1 x 10-9m)

Frequency is defined as the number of waves that pass a given point in a specific time, usually one second. One wave per second is called hertz. Longer wave length means that the wave has a lower frequency.

Frequency and wavelength are related to each other and for electromagnetic waves c = λ x v c is the speed of light – 300,000,000 meter per second or 3 x 108 m/s. λ is the wavelength v is the frequency.

Max Plank suggested that a hot object does not emit electromagnetic energy continuously. It should if it is in form of a wave. Objects emit energy in small, specific amounts called quanta. Quantum: A quantum is the minimum amount of energy that can be lost or gained by an atom.

E = hv E = Energy h= Plank’s constant V = frequency

Dual Nature of Light Three ways to tell a wave from a particle… Waves can bend around small obstacles… …and fan out from pinholes. Particles effuse from pinholes Three ways to tell a wave from a particle… wave behavior particle behavior waves interfere particle collide waves diffract particles effuse waves are delocalized particles are localized