SI Units

• What are the SI Base Units?

  Six fundamental units in the SI system

  
• Why are there many units in Physics?

  They can be reduced to six base units
• How many SI Base Units are officially used worldwide?

  Six SI Base Units
• What are derived units in the SI system?

  Units derived from the seven SI Base units
• What is the unit of force in the SI system?

  Newton (N)
• How is the Newton (N) defined?

  Force = mass × acceleration
• What is the equation for Newton (N) in SI base units?

  N = kg m s$^{-2}$
• What is the unit of energy in the SI system?

  Joule (J)
• How is the Joule (J) defined?

  Energy = ½ × mass × velocity
• What is the equation for Joule (J) in SI base units?

  J = kg m$^{2}$ s$^{-2}$
• What is the unit of pressure in the SI system?

  Pascal (Pa)
• How is the Pascal (Pa) defined?

  Pressure = force ÷ area
• What is the equation for Pascal (Pa) in SI base units?

  Pa = kg m$^{-1}$ s$^{-2}$
• What is necessary to deduce the base units?

  Use the definition of the quantity
• What are the first five SI base units you need to know for this course?

  1. Meter (m)
  2. Kilogram (kg)
  3. Second (s)
  4. Ampere (A)
  5. Kelvin (K)

  
• What are the derived units mentioned in the study material?

  • Newton (N): unit of force
  • Joule (J): unit of energy
  • Pascal (Pa): unit of pressure