General Knowledge

Speed of Light:             c = 3 x 10⁸ m/s  ≈ 1 ft/ns

Speed:                          1 m/s ≈ 2 mph ≈ 4 km/hr

Speed of Sound:            v_sound ≈ 340 m/s

Electron Mass:             m_e ≈ 511 keV/c²

Atomic Mass Unit        1 amu ≈ m_proton ≈ m_neutron ≈ 932 MeV/c²

Your Janitor’s name:    ?

World Population:       ≈ 7 billion people

US Population:             ≈ 300 million people

Visible Light:                400-700nm

Atomic Radius:             approx. 1 angstrom = 0.1nm

Nuclear Radius:             approx. 1 fm = 10^-15 m

  (or )