8M2 SCI

• Light – An electromagnetic wave that can travel even without a medium. It is a transverse wave, meaning it moves

  perpendicular to the direction of its propagation. It could also be made up of a particle called photons
• 1.     Reflection – The property of a wave that refers to the bouncing back of waves.
• 1.     Refraction – The bending of light when it passes through different media.
• 1.     Diffraction – The bending of a wave when it  passes through a gap or around edges.
• 1.     Polarization – The property of a light waves that allows an unpolarized light to vibrate or to focus in one direction.

  How light passes through different media:
• 1.     Opaque – Does not allow light to pass through
• 1.     Transluscent – Allows some light to pass through
• 1.     Transparent – Allows all or most light to pass through
• As the wavelength(how long the wave is) decreases, the frequency of the wave increases and so does its energy
• Red has the longest wavelength, while Violet has the shortest wavelength.
• Types of Electromagnetic Waves:

  ·       Radio Wave – Used in long distance communications

  ·       Microwave – Used in communications and cooking

  ·       Infrared – Used in transferring information and data between phones, in night vision devices, and in thermal scanners.

  ·       Visible light – A range of frequencies the human eye can detect. It is a portion in the electromagnetic spectrum.

  ·       Ultraviolet – Radiation emitted by the sun

  ·       X-ray – Used to take an image of your bones and lungs

  ·       Gamma Ray – Used in medicine for curing tumors without the risks of open surgery
• Temperature – The average kinetic energy of a system. It’s usually measured in Celsius, Fahrenheit, Kelvin (SI unit), and Rankine
• Thermal Energy – The sum of the kinetic energy and potential energy of a system. Depends on the amount of matter.
• Heat – Energy in transit. It is thermal energy that transfers from one body to another whenever there is a difference in temperatures. It flows from hotter bodies or objects to colder ones
• Thermal Equilibrium – This is when the bodies are at equal temperature, and the hotter objects stop from giving off heat.
• Effect of heat in matter:

  ·       Evaporation – Liquid to Gas

  ·       Freezing – Liquid to Solid

  ·       Melting – Solid to Liquid

  ·       Deposition – Gas to Solid

  ·       Condensation Gas to Liquid

  ·       Sublimation – Solid to Gas
• Thermal Expansion – Materials expanding when heated

  ·       Linear Expansion

  ·       Area Expansion

  ·       Volume Expansion
• Change in length (m) –$\Delta L$
• Initial Length (m) - LO
• Change in Temperature (C) - $\Delta T$
• Equality – Defined as having the same state
• Circuit – A path where charges can flow from a voltage source
• ·       Battery – The voltage source in a circuit. The longer line is positive, the shorter line is negative
• ·       Resistor – Used to reduce current flow in a circuit
• ·       Switch – Closes and opens the circuit. When the circuit is open, there is no current flowing around the circuit
• ·       Wire – The Pathway for the current to flow in the circuit
• Bulb – Turns electricity to light and then heat. One of the most common loads in an electric circuit
• Voltage – The potential difference between 2 points in an electric field
• Current – The rate of flow of electrons in a circuit
• Resistance  - When electricity flows through the circuit. It is also known as hindrance
• Ohm’s Law – Voltage is directly proportional to current under constant resistance.
• V = Voltage in Volts(V)          I = Current in Amperes(A)         R = Resistance in W
• Series Circuit – Bulbs are connected in one path. If one of the bulbs is busted, the remaining light bulbs will not light up anymore
• Parallel Circuit – Parallel circuit is a circuit where the bulbs are connected in two or more pathways.If one of the bulbs is busted, the remaining light bulbs will still light up
• Grounding – Allows a low-resistance path to Earth. It helps protect our electrical devices and appliances.
• Fuses – Electrical devices that help protect your circuit from too much current
• Voltage Protectors - devices that protect electrical equipment from power surges, spikes, and voltage fluctuations.
• Surge Protection Devices (SPDs) - used to ensure a safe voltage limit across circuits.
• Circuit Breaker - electrical safety device, a switch that automatically interrupts the current of an overloaded electric circuit, ground faults, or short circuits.