What is difference between knot and km?

Answer 1

A knot is a nautical unit of speed equal to one nautical mile per hour. The term comes from the old sailing ships where speed was determined by throwing a rope with a wedge shaped piece of wood tied to one end over the stern of the ship, and counting the number of equally spaced knots tied in the rope that fed out during a set amount of time. It is equal to 1.15 MPH or 1.85 km/h.

If you want to know the particulars, the knots were tied 14.4 meters apart and the sand clock measured out thirty seconds. One sailor threw the end of the rope into the sea while the other turned the timer over. The first sailor counted the number of knots passing through his hand until the other sailor told him to stop at the end of thirty seconds.

A nautical mile is the distance spanned by one minute of arc along a north south line passing through the north pole (a meridian), and is equal to 1.15 statute miles.

The statute mile is so named because it was standardized by an act of Parliament in 1593, i.e., a statute.

A km (kilometer) is an SI (Systeme International) unit for distance equal to 100 meters, a little less than 2/3 of a mile (0.62 mile to be more precise). The meter was originally standardized as one ten millionth of the distance along a line from the north pole passing through Lyons France (a meridian).