Question for today

Why do we need standard units?

What we know

What we know

• mass
• length
• time
• temperature
• amount of substance
• electrical current
• luminous intensity

What we know

• mass  [kilogram - kg]
• length [metre - m]
• time [second - s]
• temperature [kelvin K]
• amount of substance [mole mol]
• electrical current [ampere - A]
• luminous intensity [candela - cd]