Energy is the ability to do work.There are two basic types of energy:

1. Kinetic Energy- The energy of motion. We use this equation:

where m = mass of objectv = speed of object

2. Potential Energy- exists whenever an object which has mass has a position within a force field. We use this equation:

PEgrav = mass * g * height

What is it? Electromagnetic Radiation (EM) Consists of oscillating electric and magnetic fields (forces). Light is not composed of matter. Light is energy. Light is composed of photons (small packets of energy).

The energy of a photon can also be written as:

E = hc/Duality of light

The concept of the photon brings to question the nature of light. Light may act like waves rippling in space or the ocean. If so, this represents the wave-like property of light with constructive and destructive interference. Or light may act similar to a bullet and actually cause matter be relocated. This represents the particle like property of light. The latter property can be explained by the Photoelectric effect.

c is the speed of light in a vacuum 3x108 m/s

And is the wavelength

Energy can be transformed into matter with enough speed.

If you use just the right wavelength on just the right material, the energy can be transferred to the matter. In some cases ejecting an electron. This is how your remote control, TV, microwave and many other devices work.

hv

E -

Specific metalSpecific color of light

Electromagnetic Radiationthe visible spectrum

R O Y G B I V

E R E R L N I

D A L E U D O

N L E E I L

G O N G E

E W O T

The human eye can only see the blend of colors. White light is really composed all the above wavelengths.

The first clue to understanding the role of the electron in the modern atom came from studying the line spectrum of the elements.

Bohr imagined the electron moving around the nucleus in circular orbits corresponding to various allowed energy levels. Electrons can only be in “specific or discrete” energy levels. All other values or “orbits” are not possible. These levels are said to be “quantized”. The energy of an electron can only change via a transition. They are not continuous. Bohr’s model works well for hydrogen but fails for heavier atoms.