Day d
About the Day
As a unit accepted for use with the SI, the day is exactly 86,400 seconds. The actual solar day varies slightly and the Earth's rotation is gradually slowing, which is why leap seconds have been inserted into UTC since 1972. Calendars count whole days as their basic building block.
Related Units
Second
sBase unit; caesium-133 frequency = 9,192,631,770 Hz exactly
The second is defined by taking the unperturbed ground-state hyperfine transition frequency of the caesium-133 atom to...
Hertz
Hz1 Hz = 1 s⁻¹
The hertz is one cycle or event per second and replaced the older expression cycles per second. It is named after...
Julian year
a365.25 d = 31,557,600 s (exact)
In astronomy the Julian year is exactly 365.25 days of 86,400 seconds, or 31,557,600 seconds. It is the year used to...
Litre
L1 L = 1 dm³ = 0.001 m³ (exact)
The litre is a cubic decimetre, a cube 10 centimetres on each side. From 1901 to 1964 it was defined as the volume of...