1.1 SI Units and Prefixes

• There are seven base SI units.

  True
• What is 1 kilometre equal to in metres?

  1000 metres
• The prefix micro represents a power of 10⁻⁶
• What does SI stand for?

  International System of Units
• The prefix kilo represents a power of 1000
• The SI units are used to measure fundamental physical quantities.


  True
• What is the base SI unit for length?

  metre
• Match the physical quantity with its corresponding base SI unit:

  Length ↔️ metre

  Mass ↔️ kilogram

  Time ↔️ second

  Electric current ↔️ ampere
• How many base SI units are there?

  Seven
• What is the base SI unit for mass?

  kilogram
• The base SI unit for time is the second
• Match the derived SI unit with its formula:

  Speed ↔️ m/s

  Force ↔️ kg × m/s²

  Power ↔️ J / s

  Density ↔️ kg/m³
• What is the prefix for 10⁻³?

  milli
• 12 micrograms is equal to 0.000012 grams.


  True
• How many metres are in 5 kilometres?

  5000 m
• Match the quantity with its SI unit and abbreviation:

  Length ↔️ metre ||| m

  Mass ↔️ kilogram ||| kg

  Time ↔️ second ||| s

  Temperature ↔️ kelvin ||| K
• Base SI units can be combined using prefixes to represent multiples and sub-multiples
• The SI unit for length is the metre, abbreviated as 'm'


  True
• Match the derived SI unit with its quantity and formula:

  Area ↔️ square metre ||| m² ||| length × length

  Volume ↔️ cubic metre ||| m³ ||| length × width × height

  Density ↔️ kilograms per cubic metre ||| kg/m³ ||| mass / volume

  Force ↔️ newton ||| N ||| kg × m/s²
• SI unit prefixes are based on powers of ten
• What is the power of ten associated with the prefix 'kilo'?

  10³
• Understanding SI prefixes is crucial for unit conversions in physics.

  True
• One megawatt (MW) is equal to one million watts (W).


  True
• One megawatt (MW) is equal to 1,000,000 watts (W).
• What is the power of ten associated with the prefix 'milli'?

  10⁻³
• Order the prefixes from largest to smallest in terms of their powers of ten:

  1️⃣ mega

  2️⃣ kilo

  3️⃣ milli

  4️⃣ micro
• What is the power of ten associated with the prefix 'kilo'?

  10³
• What is the base SI unit for temperature?

  kelvin
• How are derived SI units obtained?

  Combining base SI units
• 1 megawatt is equal to 1,000,000 watts.


  True
• How many metres are there in 5 kilometres?

  5000 metres
• Match the prefix with its symbol and power of 10:

  kilo ↔️ k ||| 10³

  mega ↔️ M ||| 10⁶

  milli ↔️ m ||| 10⁻³

  micro ↔️ µ ||| 10⁻⁶
• Mastering prefix conversions is key to working with different units in physics and other sciences
• What is the abbreviation for kelvin?

  K
• How many base SI units are there?

  Seven
• What are derived SI units used to measure?

  Complex physical quantities
• Derived SI units are constructed by combining base SI units


  True
• How many grams are in 1 microgram?

  0.000001 g
• What is the power of ten associated with the prefix 'milli'?

  10⁻³
• What does the prefix 'kilo' mean in SI units?

  10³