Light

Electromagnetic Spectrum Light is an electromagnetic energy. Travels in the form of an electromagnetic wave. Chapter 19 Sections: 1, 5, 6, 8, 9, 10 Chapter 20 Sections: 2, 4, 5, 6, 7, 8, 9

Electromagnetic Spectrum Chapter 19 Sections: 1, 5, 6, 8, 9, 10 Chapter 20 Sections: 2, 4, 5, 6, 7, 8, 9

Photosynthesis Plants use light energy to make food for itself in a process called photosynthesis. 6CO2 6H2O 6CO2 6H2O C6H12O6 + Chapter 19 Sections: 1, 5, 6, 8, 9, 10 Chapter 20 Sections: 2, 4, 5, 6, 7, 8, 9 6O2

How Do Lenses Refract Light? Lens is a transparent material that refracts light. Virtual Image focus Chapter 19 Sections: 1, 5, 6, 8, 9, 10 Chapter 20 Sections: 2, 4, 5, 6, 7, 8, 9 focus Real Image Object Object

How Do Mirrors Reflect Light? When light strikes a smooth surface the light is reflected. This type of reflection is called a regular reflection. If light strikes a rough surface it will be reflected at many different angles forming a diffuse reflection. Chapter 19 Sections: 1, 5, 6, 8, 9, 10 Chapter 20 Sections: 2, 4, 5, 6, 7, 8, 9

What is Color? Chapter 19 Sections: 1, 5, 6, 8, 9, 10

Chapter 19 Sections: 1, 5, 6, 8, 9, 10 Chapter 20 Sections: 2, 4, 5, 6, 7, 8, 9

How Can Light Be Used? Laser: device that produces a very powerful intense beam of same color light. Uses Medicine Industry Military Fiber optics

How Fiber Optics Work Fiber optic cable Location A Location B

What is an Electric Charge? Electricity is the flow of negative charges from a place of higher concentration to a lower concentration. + + + + + + + +

Electric Battery Batteries are made using 1) + Electrode 2) – Electrode 3) Electrolyte + carbon electrode - zinc electrode + copper electrode - zinc casing Electrolyte (acid or base) Moist paste

Electric Current Types Direct Current (DC) Current flows one way. Electric current found in dry cells. Alternating Current (AC) Constantly changes direction at a constant rate. Advantage is that it can be sent over long distances. Voltage can be increased / decreased

Series Circuit A circuit needs three things. Energy source Path Load Series circuit: circuit in which current only flows in one direction. - - - - -

Parallel Circuit Parallel circuit- circuit in which electric current can follow more than one path.

Measure Electricity Voltage: energy that is available to push electrons through the path. Measured in volts (V) by a voltmeter. Current: amount of electric current. Measured in amps (A) by an ammeter. Resistance: material that resists the flow of electricity. Measured in ohms (Ω). Length, diameter, material, and temperature affect amount of resistance.

Voltage = 6 amps × 10 Ω Voltage = 60 Volts Ohm’s Law: current in a wire is equal to the voltage divided by the resistance. Voltage = 6 amps × 10 Ω Voltage = 60 Volts 6 A - - - 2 Ω 3 Ω 5 Ω - - - - - 6 A