IB Physics HL

• What is the topic of the first section in the study material?

  Measurement and uncertainties
• What are the fundamental SI units listed in the study material?


  • Mass: Kilogram (kg)
  • Distance: Meter (m)
  • Time: Second (s)
  • Electric current: Ampere (A)
  • Amount of substance: Mole (mol)
  • Temperature: Kelvin (K)
• What are derived units?


  Derived units are combinations of fundamental units.
• What is the unit for velocity?


  m/s
• What is the unit for force?


  N (Newton)
• What is the unit for energy?

  J (Joule)
• How is scientific notation expressed?


  In the form a*10^n, where a is between 1 and 10 and n is an integer.
• How is the speed of light expressed in scientific notation?


  3*10^8 m/s
• How is 1 centimeter expressed in scientific notation?


  1*10^-2 m
• What are the metric multipliers and their values?


  • Peta (P): 10^15
  • Tera (T): 10^12
  • Giga (G): 10^9
  • Mega (M): 10^6
  • Kilo (k): 10^3
  • Hecto (h): 10^2
  • Deca (da): 10^1
  • Deci (d): 10^-1
  • Centi (c): 10^-2
  • Milli (m): 10^-3
  • Micro (μ): 10^-6
  • Nano (n): 10^-9
  • Pico (p): 10^-12
  • Femto (f): 10^-15
• What are significant figures?


  Significant figures are the digits in a number that contribute to its precision.
• What are the exceptions for significant figures?


  Leading zeros and trailing zeros without a decimal point are not significant.
• How many significant figures does the number 12300 have?


  3 significant figures
• How many significant figures does the number 012300 have?


  5 significant figures
• How should the number of significant figures in a result be determined?


  It should not exceed the least precise value of the calculation.
• What is the rule for significant figures in multiplication and division?


  Give the answer to the lowest significant figure.
• What is the rule for significant figures in addition and subtraction?


  Give the answer to the lowest decimal place.
• What are orders of magnitude?


  • Given in powers of 10
  • Used to compare the size of physical data
• What are the orders of magnitude for distance in meters?


  • Diameter of the observable universe: 10^26
  • Diameter of the Milky Way galaxy: 10^21
  • Diameter of the Solar System: 10^13
  • Distance to the Sun: 10^11
  • Radius of the Earth: 10^7
  • Diameter of a hydrogen atom: 10^-10
  • Diameter of a nucleus: 10^-15
  • Diameter of a proton: 10^-15
• What are the three states of matter mentioned in the study material?


  Solids, liquids, and gases
• What are the orders of magnitude for mass in kilograms?


  • The universe: 10^53
  • The Milky Way galaxy: 10^41
  • The Sun: 10^30
  • The Earth: 10^24
  • A hydrogen atom: 10^-27
  • An electron: 10^-30
• What holds molecules together in solids, liquids, and gases?

  Intermolecular forces
• What are the orders of magnitude for time in seconds?


  • Age of the universe: 10^17
  • One year: 10^7
  • One day: 10^5
  • An hour: 10^3
  • Period of heartbeat: 10^0
• Is the fourth state of plasma required to be learned in the current syllabus?


  No, it is not required
• How are estimations typically made?


  Estimations are usually made to the nearest power of 10.
• What does temperature describe in relation to heat flow?


  It describes how hot or cold an object is and determines the direction of heat flow
• What are the differences between random and systematic errors?

  Random errors:

  • Caused by fluctuations in measurements
  • Can be reduced by averaging
  • Not caused by bias

  
  

  Systematic errors:

  • Caused by fixed shifts in measurements
  • Cannot be reduced by averaging
  • Caused by bias
• From which object does thermal energy transfer?


  From an object with higher temperature to one with lower temperature
• What is an example of a random error?


  Fluctuations in room temperature
• What is the term for the energy transfer due to temperature difference?


  Heat
• What is an example of a systematic error?


  Equipment calibration error such as the zero offset error
• What does it mean for objects to be in thermal equilibrium?


  They have the same temperature
• How are physical measurements expressed with uncertainties?


  In the form x±Δx, where:

  • x is the measured value
  • Δx is the absolute uncertainty
• What is absolute uncertainty?


  Absolute uncertainty is the range of values around a measurement.
• How can temperatures in Kelvin be calculated from Celsius?


  By adding 273.15 to the Celsius temperature
• What is the relationship between absolute temperature and average kinetic energy?


  Absolute temperature is directly proportional to the average kinetic energy per molecule
• What is fractional uncertainty?

  Fractional uncertainty is calculated as Δx/x.
• What is the value of absolute zero in Kelvin and Celsius?


  0 K or -273 degrees Celsius
• What is percentage uncertainty?


  Percentage uncertainty is calculated as $\frac{\Delta x}{x} \times 100\%$.
• Can temperatures be lower than absolute zero?


  No, temperatures cannot be lower than absolute zero