Physics

• Length


  A fundamental physical quantity that represents the extent of an object in one dimension
• Units of Length


  • meters (m)
  • centimeters (cm)
  • kilometers (km)
• Area


  A measure of the size of a two-dimensional surface or shape
• Units of Area


  • square meters (m^2)
  • square centimeters (cm^2)
  • square kilometers (km^2)
• Volume


  A measure of the amount of space occupied by a three-dimensional object
• Units of Volume


  • cubic meters (m^3)
  • cubic centimeters (cm^3)
  • liters (L)
• Measuring Instruments


  • Rulers
  • Tape measures
  • Calipers
  • Micrometers
  • Laser distance meters
  • Planimeters
  • Measuring cups
  • Beakers
  • Graduated cylinders
  • Pipettes
  • Burettes
• Determining Lengths, Surface Areas, and Volumes

  1. Regular Bodies: Use well-defined formulas

  2. Irregular Bodies: Use integration, approximation, or modeling with simpler shapes
• Mass


  A fundamental physical quantity that represents the amount of matter in an object
• Units of Mass


  • kilogram (kg)
  • gram (g)
• Beam Balances


  Types of weighing scales that use a horizontal beam supported by a pivot point to compare the mass of an unknown object with a known standard mass
• Beam Balances


  • Buchart's balance
  • Chemical balances
• Time


  A fundamental physical quantity that measures the duration of events
• Units of Time


  • second (s)
• Time-Measuring Devices


  • Clocks
  • Stopwatches
  • Timers
  • Sundials
• Physical Quantities


  Described by numerical values and units that represent their magnitudes and dimensions
• Derived Physical Quantities


  Combinations of fundamental quantities that have specific units derived from their defining equations
• Derived Physical Quantity


  • Velocity (meters per second, m/s)
• Dimensions


  The nature of physical quantities without numerical values, representing the fundamental properties of quantities based on their fundamental units
• Dimensions


  • Length [L]
  • Time [T]
• Determining Dimensions of Physical Quantities

  1. Analyze the equations that define physical quantities

  2. Express dimensions in terms of fundamental units like length, mass, and time
• Using Dimensions to Determine Units of Physical Quantities


  Match the dimensions on both sides of an equation to deduce the units of derived quantities
• Homogeneity of an Equation

  The dimensions of all terms on both sides of the equation are consistent
• Limitations of Experimental Measurements

  • Accuracy of measuring instruments
  • Precision of measurements
  • Systematic and random errors
• Scalar quantities


  Quantities that have only magnitude, like temperature or mass
• Vector quantities


  Quantities that have both magnitude and direction, like velocity or force
• Scalar quantities


  • distance
  • time
  • temperature
• Vector quantities


  • displacement
  • velocity
  • acceleration
• Determining the resultant of two or more vectors

  1. Draw the vectors to scale

  2. Place them head to tail

  3. Draw the resultant vector from the tail of the first vector to the head of the last vector
• Relative velocity


  The velocity of an object as observed from another moving object
• Determining relative velocity


  Subtract the velocity of one object from the velocity of the other object
• Resolving vectors into two perpendicular components

  Use trigonometry
• Graphical methods


  Used to solve vector problems by drawing vector diagrams and using geometric techniques to find the desired quantities
• Types of Motion


  • Translational Motion
  • Rotational Motion
  • Oscillatory Motion
  • Circular Motion
  • Rectilinear Motion
  • Curvilinear Motion
• Translational Motion


  An object moves in a straight line, like a car driving on a highway
• Rotational Motion


  An object spins or rotates around an axis, like a spinning top or a rotating fan
• Oscillatory Motion


  A back-and-forth motion around a central point, like a pendulum swinging or a vibrating guitar string
• Circular Motion


  An object moves in a circular path, like a planet orbiting the sun or a car going around a roundabout
• Rectilinear Motion


  Motion where an object moves in a straight line, but not necessarily at a constant speed
• Curvilinear Motion


  An object moves along a curved path, like a car taking a turn on a winding road