Speed Unit Conversion Chart

What is Speed?

Speed is actually about how much movement through what time time or how far you can go in a certain amount of time. Speed can be thought of as the rate at which an object covers distance. A fast-moving object has a high speed and covers a relatively large distance in a short amount of time. A slow-moving object has a low speed and covers a relatively small amount of distance in a short amount of time. An object with no movement at all has a zero speed.

Usually the time part is the fixed bit i.e a second or an hour or a millisecond, then you measure how much the item moves in that chosen time. hence this car is moving at 6 miles per hour, or even this light wave oscillates at x times per second.

Definition

The speed v is defined as the magnitude of the velocity v, that is the derivative of the position r with respect to time:

If s is the length of the path traveled until time t, the speed equals the time derivative of s:

In the special case where the velocity is constant (that is, constant speed in a straight line) this can be simplified to v=s/t. The average speed over a finite time interval is the total distance traveled divided by the time duration. wikipedia

Speed Unit

Speed has the dimensions of a length divided by a time; the SI unit of speed is the meter per second, but the most usual unit of speed in everyday usage is the kilometer per hour or, in the USA and the UK, miles per hour. For air and marine travel the knot is commonly used.

Some unit of speed:

    * Meters per second (symbol m s^-1 or m/s), the SI derived unit;
    * Kilometers per hour (symbol km/h);
    * Miles per hour (symbol mph);
    * Knots (nautical miles per hour, symbol kn or kt);
    * Feet per second (symbol fps or ft/s);
    * Mach number, speed divided by the speed of sound;
    * The speed of light in vacuum (symbol c) is one of the natural units: c = 299,792,458 m/s

Conversions between common units of speed

	m/s	km/h	mph	knot	ft/s
1 m/s =	1	3.6	2.236936	1.943844	3.280840
1 km/h =	0.277778	1	0.621371	0.539957	0.911344
1 mph =	0.44704	1.609344	1	0.868976	1.466667
1 knot =	0.514444	1.852	1.150779	1	1.687810
1 ft/s =	0.3048	1.09728	0.681818	0.592484	1

 

Speed Unit Conversion Table

Unit	Symbol	Definition	Conversion to SI units
foot per hour	fph	= 1 ft/h	~ 8.466 667 x 10-5 m/s
foot per minute	fpm	= 1 ft/min	= 5.08 x 10-3 m/s
foot per second	fps	= 1 ft/s	= 3.048 x 10-1 m/s
furlong per fortnight		= furlong/fortnight	~ 1.663 095 x 10-4 m/s
inch per minute	ipm	= 1 in/min	~ 4.23 333 x 10-4 m/s
inch per second	ips	= 1 in/s	= 2.54 x 10-2 m/s
kilometre per hour	km/h	= 1 km/h	~ 2.777 778 x 10-1 m/s
knot	kn	= 1 NM/h = 1.852 km/h	~ 0.514 444 m/s
knot (Admiralty)	kn	= 1 NM (Adm)/h = 1.853 184 km/h	= 0.514 773 m/s
mach number	M	Ratio of the speed to the speed of sound in the medium. Varies especially with temperature. About 761 mph (1225 kph) in air at sea level to about 660 mph (1062 kph) at jet altitudes. Unitless	~ 340 to 295 m/s for aircraft
metre per second (SI unit)	m/s	= 1 m/s	= 1 m/s
mile per hour	mph	= 1 mi/h	= 0.447 04 m/s
mile per minute	mpm	= 1 mi/min	= 26.8224 m/s
mile per second	mps	= 1 mi/s	= 1 609.344 m/s
speed of light in vacuum	c	= 299 792 458 m/s	= 299 792 458 m/s
speed of sound in air	s	Varies especially with temperature. About 761 mph (1225 kph) in air at sea level to about 660 mph (1062 kph) at jet altitudes.	~ 340 to 295 m/s at aircraft altitudes