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Physics notes(Lewis) - Coggle Diagram

- - - - Physics is the study of Matter and energy
        
        Matter can be studied in terms of its:
        
        Properties and relationship with energy
        
        Energy can be studied in terms of its:
        
        Properties and relationship with matter
        
        The relationship with energy and matter can be expressed through:
        
        Light, waves and Sound
        
        Electricity and Magnetism
        
        Thermal physics
        
        Radioactivity
        
        General physics
    - - What are Physical quantities?
        
        A physical quantity refers to something that can be measured. It usually consists of a magnitude and unit
        
        Example: 40g
        
        The 40 refers to the physical quantities magnitude
        
        The g which stands for grams refer to its unit
        
        Physical quantities can be classified into 2 other quantities
        
        Base quantities:
        
        Base quantities refers to basic/ fundamental quantities such as:
        
        Time
        
        Electric current
        
        Temperature
        
        Luminous intensity
        
        Mass
        
        Amount of substances
        
        Length
        
        Base quantities are also the building blocks for Derived quantities
        
        Derived quantities:
        
        Derived quantities are quantities that can be derived from fundamental quantities such as length and time
        
        Some examples of derived quantities include:
        
        Area in metre² (m²)
        
        Area= length x breadth
        unit of area = unit of length x unit of breadth = m x m = m²
        
        Volume in metre³ (m³)
        
        Volume = length x breadth x height
        unit of volume = unit of length x unit of breadth x unit of height = m x m x m= m³
        
        Speed in metre/second (m/s)
        
        Speed = distance/time
        unit of speed = unit of distance/unit of time = m/s
      - What are SI units?
        
        SI Units( International system of units) refer to one universal set of units that were agreed upon by scientists to standardize measurements.
        
        Length in Metres(M)
        
        Mass in Kilograms(Kg)
        
        Time in Seconds(s)
        
        Electric current in Ampere(A)
        
        Temperature in Kelvin(K)
        
        Luminous intensity in Candela(cd)
        
        Amount of substances in Mole(mol)
      - What are Prefixes and standard form?
        
        Prefixes
        
        Prefixes are a letter added to the beginning of units to indicate multiples or fractions of the unit
        
        Prefixes usually come in the form of specific factors that come in the form of 10³(Kg) etc
        
        Standard form
        
        Expressing long values in terms of standard form is a way of shortening or simplifying expressions.
        
        Standard form can be expressed through this formula:
        x x 10^n
        
        Where must be an integer between 1.0 and 10.0 while also be an integer
    - - Instruments to measure length
        
        Measuring tape(Not in syllabus)
        
        Suitable for measuring a few metres with a precision of 0.1cm
        eg. Dimensions of a room
        
        Metre rule(Not in syllabus)
        
        Suitable for measuring up to one metres with a precision of 0.1cm
        eg. Thickness of a book
        
        Digital calipers(Tested in syllabus)
        
        Suitable for measuring up to a few centimetres with a precision of 0.001cm or 0.01mm
        eg.Thickness of a phone
        
        Digital Micrometre screwgauge
        (Tested in syllabus)
        
        Suitable for measuring a few milimetres with a precision of 0.0001cm or 0.001mm
      - Small note to self(AKA Lewis)
        
        Precision stands for the smallest unit an instrument is able to measure. If you have any questions then look at your ruler and you can see that it measures out to o.1cm or 1mm
      - Errors while using the instruments
        
        Parallax error
        
        Occurs when you misalign your eye with the readings on an instrument. Usually occurs on Metre rules and measuring tapes
        
        Zero error
        
        Occurs when an instrument gives a non-zero reading when the reading is supposed to be zero. For example: The ruler might be slightly worn out and the reading at zero is not clear/ thorn off.
        
        Experimental error(additional)
        
        Experimental errors are unavoidable while conducting experiments related to measurements. Eg. A human timing a stopwatch and stopping it inaccurratedly by 0.1 seconds
        
        Note to self(Lewis)
        
        Both Zero errors and Parallax errors are very easily avoidable so it shouldn't be written when a question asks you what types of errors can easily occur in experiments.
      - How to use digital calipers and Micrometer Gauge?
        
        Hippie watch a video cause the editor is too lazy or whatever. I won't provide links.
    - - What are Pendulums?
        
        Pendulums are balls of steels attached to strings that can be used to measure a fixed interval of time
        
        There are 2 terms about pendulums that you must know of:
        
        Oscilation
        
        Refers to one complete to-and-fro motion of a pendulum
        
        Period
        
        The period is the time taken for 1 oscilation to happen
        
        Formula to measure the period:
        
        T=2π√L/g
        
        Where T is the period and L is the length of the string while g is the gravitational field strength
  - - - What is kinematics?
        
        Kinematics refers to the study of the motion of objects
        
        Example: Speed of Usain bolt sprinting
    - - A physical quantity can be classified whether it is scalar or Vector
        
        What are scalar quantities?
        
        Scalar quantities are physical quantities that only have a magnitude but no direction
        
        Examples include: Time, Length and Temperature
        
        What are Vector quantities?
        
        Vector quantities are physical quantities that possess a magnitude and direction
        
        Examples include: Force and velocity
      - Distance vs Displacement(Vry Important):
        
        Distance
        
        Distance refers to the length that a moving object covers along a path taken regardless of the direction of motion
        
        Distance is a scalar quantity
        
        Displacement
        
        Refers to the length covered by a moving object in a straight line and in a specified direction from the starting origin to the end point
        
        Displacement on the other hand is a vector quantity
        
        Take note(Lewis)
        
        No displacement will occur if you travel in a circle
    - - Speed
        
        Refers to the rate of change of distance
        Speed is a scalar quantity
        
        The SI unit of speed is m/s or ms^-1
      - Velocity
        
        refers to the rate of change of Displacement
        Velocity is a vector quantity
        
        In questions related to velocity, the conventions and the sign(+ or -) must be defined
        
        The SI unit of velocity is also m/s or ms^-1