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Eng Sci Y8 Q3+Q4 - Coggle Diagram

- - - - the universe start from a substance extremely small and hot
      - Afterwards, stars, planets, moon, and stars were formed. The universe will be expanding forever, despite it decelerating.
      - The universe exponentially expanded and cooled
      - energy changed into particles, making atoms such as hydrogen and helium
    - - when the hydrogen fuel of the star uses up, they turn into a red giant
      - the center of the red giant will shrink, becoming a white dwarf
      - the white dwarf cools and becomes a black dwarf
    - - causes mass-extinction (the dust caused by impact blocks radiation, causing earth's climate to drop)
      - forms the moon (lighter rock of the asteroid thrown out of orbit and forms the moon)
      - the crater depends on the asteroid's mass, size, and direction
  - - - measured in amps using an ammeter, unit: A
      - ammeter placed in series behind the object you measure
    - - measured in volts using a voltmeter, unit: V
      - voltmeter placed in parallel behind the object you measure
    - - Resistance = Voltage/ Current OR R=V/I
      - measured in ohms
    - - In parallel circuit, the current is shared while the voltage is the same
      - In series circuit, the current is same while the voltage is shared
      - shared: sum of the (unit) of branch circuits = (unit) of the main circuit
      - same: the (unit) is equal in every part of the circuit
      - resistance determines the voltage
  - - - Power=Energy/Time
      - measured in watts, unit: W
      - one watt= one joule per second
      - Def: the rate of energy transferred in a certain period of time
    - - Conduction
        
        It can transfer in solid (liquid and gas are poor conductors)
        
        How? travel from particle to particle in its vibration distance
        
        Slower than convection, because it transfers through direct contact between materials
      - Convection
        
        It can only transfer in heated liquid or solid
        
        How? the particle with greater thermal energy replaces a particle with less thermal energy
        
        Why? When particles get heated, they expand, got less dense, and rise, forming a convection current in the liquid or gas. The circulation helps to distribute the hot particles more evenly. Increasing the temperature
        
        More efficient than conduction, because of the movement of fluids
      - Radiation
        
        How? in electromagnetic waves without the need of medium. It can transfer in solid, liquid, gas, and vacuum.
        
        3 important features
        
        reflected (white surface especially)
        
        transmitted/emitted
        
        absorbed (black surface especially)
        
        Electromagnetic Spectrum
        
        (slowest, not harmful) radio wave < Microwave < Infrared < visible light < ultraviolet < X-rays < Gamma (fastest, harmful)
      - Determined by: density, chemical structure, states, heat capacity, ,surface area, and etc.
      - Cooling by evaporation explained
        
        •Average speed of the particles depends on the temperature of the liquid. (Higher Temp Higher Speed)
        
        • The particles are colliding with each other, and energy is transferred in those collisions.
        
        • A few of the particles at the surface will be travelling fast enough to be able to turn into gas.
        
        • When fast-moving particles escape, the average speed of the particles left behind is slower --> colder
      - Thermal insulator traps thermal energy while thermal conductor transfers energy easily
    - - heat: thermal energy
      - temperature: the measure of heat (unit: Fº or Cº)
      - dissipation: thermal energy transfer from high temperature region to low temperature region (it is a natural tendency)
      - thermal equilibrium: eventual state of energy transfer in which objects that are in thermal contact reached a balanced temperature everywhere
    - - Sankey diagram
        
        LHS (energy input) can be electrical, thermal, and chemical
        
        RHS (energy output) can be light, sound and heat
      - Law of energy conservation: Energy cannot be created / destroyed, it can only be transferred
      - wanted energy output: "useful" unwanted energy output: "wasted"
      - Efficiency (in percentage)= useful energy / total energy output
  - - - Crest: highest point
      - Trough: lowest point
      - Wavelength: distance between corresponding points
      - Amplitude: maximum distance moved by a point (determines loudness of sound wave)
      - Frequency: rate of vibration (determines pitch of sound wave)
      - Ultrasonic Sounds: sound with frequency higher than audible sounds
      - Decibel: unit used to measure the intensity of a sound wave
      - Hertz: unit of frequency
- - - - discontinuous: completely inherited (such as blood type)
      - Continuous: takes place because of the interaction between genetics and the environment (such as height)
    - - adaptations: changes that living organism make to survive and adapt the environment to pass on their DNA
      - Def: nature select the genetic compositions / survival of the fittest
      - populations that don't survive successfully in their environment...
        
        extinct: dying of a species
        
        endangered: vulnerable, threatened, low population
  - - - Plants
        
        photosynthesis: the plant transfers atmospheric CO2 and water to oxygen and glucose (requires chlorophyll)
        
        feeds the animal
        
        After death:
        
        decomposition/decay: break down from big molecules to small molecules and recycled into simpler matter like CO2
        
        fossilization: when the dead organism is protected and under great pressure for thousands of years, it turns into a fossil
        
        combustion
        
        releases CO2
        
        must involve: heat, oxygen, and fuel
        
        excretion: when organisms excrete waste materials, they release carbon compounds when broken down by decomposers
        
        respiration: the plant obtains energy through oxygen, while producing atmospheric CO2 (requires mitochondria)
      - Animals
        
        respiration: the animal obtains energy through energy, while producing atmospheric CO2 (requires mitochondria)
      - Decomposers
        
        decomposes/break down the dead organisms and convert them into CO2
    - - Photosynthesis: carbon dioxide+water => oxygen + glucose
      - Respiration: oxygen+glucose => carbon dioxide + water+energy
      - Combustion: oxygen + fuel => carbon dioxide + water + product