Basic International System of Units

Question 1

SI-units

Answer 1

Length - metre (m)
Mass - kilogram (kg)
Time - seconds (s)
Electric Current - Ampere (A)
Temperature - Kelvin (K)
Amount of Substance - mole (mol)
Luminous Intensity - Candela (cd)

Question 2

Energy Units

Answer 2

1J = 1kgm(2)/s2
1J = N/A = Energy consumption of a bee for flying 120 m
1kJ = 10(3)J = Swimming of 1 m
1MJ = 10(3)kJ = Doing nothing for 3.5 hours (metabolic rate at rest)
1kWh = 3600 kJ = 16 hours (light bulb, 60 W), 100 hours (energy savings lamp, 10 W)
1EJ = 10(18)J = 541 EJ is the worldwide primary energy demand

Question 3

Approximate energy content of solid fuels

Answer 3

coal = 10 kWh/kg
oil = 10 kWh/l
natural gas = 10 kWh/m(3)
wood pellets = 5 kWh/kg