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In kinematics, the speed (commonly referred to as v) of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time; it is thus a non-negative scalar quantity. The average speed of an object in an interval of time is the distance travelled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero. Speed is the magnitude of velocity (a vector), which indicates additionally the direction of motion.
Speed | |
---|---|
![]() 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 given amount of time, while a slow-moving object covers a relatively small amount of distance in the same amount of time. | |
Common symbols | v |
SI unit | m/s, m s−1 |
Dimension | L T−1 |
Speed has the dimensions of distance divided by time. The SI unit of speed is the metre per second (m/s), but the most common unit of speed in everyday usage is the kilometre per hour (km/h) or, in the US and the UK, miles per hour (mph). For air and marine travel, the knot is commonly used.
The fastest possible speed at which energy or information can travel, according to special relativity, is the speed of light in vacuum c = 299792458 metres per second (approximately 1079000000 km/h or 671000000 mph). Matter cannot quite reach the speed of light, as this would require an infinite amount of energy. In relativity physics, the concept of rapidity replaces the classical idea of speed.
Definition
Historical definition
Italian physicist Galileo Galilei is usually credited with being the first to measure speed by considering the distance covered and the time it takes. Galileo defined speed as the distance covered per unit of time. In equation form, that is where is speed,
is distance, and
is time. A cyclist who covers 30 metres in a time of 2 seconds, for example, has a speed of 15 metres per second. Objects in motion often have variations in speed (a car might travel along a street at 50 km/h, slow to 0 km/h, and then reach 30 km/h).
Instantaneous speed
Speed at some instant, or assumed constant during a very short period of time, is called instantaneous speed. By looking at a speedometer, one can read the instantaneous speed of a car at any instant. A car travelling at 50 km/h generally goes for less than one hour at a constant speed, but if it did go at that speed for a full hour, it would travel 50 km. If the vehicle continued at that speed for half an hour, it would cover half that distance (25 km). If it continued for only one minute, it would cover about 833 m.
In mathematical terms, the instantaneous speed is defined as the magnitude of the instantaneous velocity
, that is, the derivative of the position
with respect to time:
If is the length of the path (also known as the distance) travelled until time
, the speed equals the time derivative of
:
In the special case where the velocity is constant (that is, constant speed in a straight line), this can be simplified to . The average speed over a finite time interval is the total distance travelled divided by the time duration.
Average speed
![image](https://www.english.nina.az/wikipedia/image/aHR0cHM6Ly93d3cuZW5nbGlzaC5uaW5hLmF6L3dpa2lwZWRpYS9pbWFnZS9hSFIwY0hNNkx5OTFjR3h2WVdRdWQybHJhVzFsWkdsaExtOXlaeTkzYVd0cGNHVmthV0V2WTI5dGJXOXVjeTkwYUhWdFlpOWhMMkV3THpJd01qTXdOekF6WDBGMlpYSmhaMlZmYzNCbFpXUmZiMlpmWW05M2JHbHVaMTlpWVd4c1gzWmxjbk4xYzE5MGNtRjJaV3hmZEdsdFpTNXpkbWN2TWpJd2NIZ3RNakF5TXpBM01ETmZRWFpsY21GblpWOXpjR1ZsWkY5dlpsOWliM2RzYVc1blgySmhiR3hmZG1WeWMzVnpYM1J5WVhabGJGOTBhVzFsTG5OMlp5NXdibWM9LnBuZw==.png)
Different from instantaneous speed, average speed is defined as the total distance covered divided by the time interval. For example, if a distance of 80 kilometres is driven in 1 hour, the average speed is 80 kilometres per hour. Likewise, if 320 kilometres are travelled in 4 hours, the average speed is also 80 kilometres per hour. When a distance in kilometres (km) is divided by a time in hours (h), the result is in kilometres per hour (km/h).
Average speed does not describe the speed variations that may have taken place during shorter time intervals (as it is the entire distance covered divided by the total time of travel), and so average speed is often quite different from a value of instantaneous speed. If the average speed and the time of travel are known, the distance travelled can be calculated by rearranging the definition to
Using this equation for an average speed of 80 kilometres per hour on a 4-hour trip, the distance covered is found to be 320 kilometres.
Expressed in graphical language, the slope of a tangent line at any point of a distance-time graph is the instantaneous speed at this point, while the slope of a chord line of the same graph is the average speed during the time interval covered by the chord. Average speed of an object is Vav = s÷t
Difference between speed and velocity
Speed denotes only how fast an object is moving, whereas velocity describes both how fast and in which direction the object is moving. If a car is said to travel at 60 km/h, its speed has been specified. However, if the car is said to move at 60 km/h to the north, its velocity has now been specified.
The big difference can be discerned when considering movement around a circle. When something moves in a circular path and returns to its starting point, its average velocity is zero, but its average speed is found by dividing the circumference of the circle by the time taken to move around the circle. This is because the average velocity is calculated by considering only the displacement between the starting and end points, whereas the average speed considers only the total distance travelled.
Tangential speed
![image](https://www.english.nina.az/wikipedia/image/aHR0cHM6Ly93d3cuZW5nbGlzaC5uaW5hLmF6L3dpa2lwZWRpYS9pbWFnZS9hSFIwY0hNNkx5OTFjR3h2WVdRdWQybHJhVzFsWkdsaExtOXlaeTkzYVd0cGNHVmthV0V2WTI5dGJXOXVjeTkwYUhWdFlpOHhMekUwTDBGdVozVnNZWEl0WVc1a0xYUmhibWRsYm5ScFlXd3RjM0JsWldRdWMzWm5Mek16TUhCNExVRnVaM1ZzWVhJdFlXNWtMWFJoYm1kbGJuUnBZV3d0YzNCbFpXUXVjM1puTG5CdVp3PT0ucG5n.png)
Units
Units of speed include:
- metres per second (symbol m s−1 or m/s), the SI derived unit;
- kilometres per hour (symbol km/h);
- miles per hour (symbol mi/h or mph);
- knots (nautical miles per hour, symbol kn or kt);
- feet per second (symbol fps or ft/s);
- Mach number (dimensionless), speed divided by the speed of sound;
- in natural units (dimensionless), speed divided by the speed of light in vacuum (symbol c = 299792458 m/s).
m/s | km/h | mph (mi/h) | knot | fps (ft/s) | |
---|---|---|---|---|---|
1 m/s = | 1 | 3.600000 | 2.236936* | 1.943844* | 3.280840* |
1 km/h = | 0.277778* | 1 | 0.621371* | 0.539957* | 0.911344* |
1 mph (mi/h) = | 0.44704 | 1.609344 | 1 | 0.868976* | 1.466667* |
1 knot = | 0.514444* | 1.852 | 1.150779* | 1 | 1.687810* |
1 fps (ft/s) = | 0.3048 | 1.09728 | 0.681818* | 0.592484* | 1 |
(* = approximate values)
Examples of different speeds
This section needs additional citations for verification.(May 2013) |
This section may contain excessive or irrelevant examples.(May 2014) |
Speed | m/s | ft/s | km/h | mph | Notes |
---|---|---|---|---|---|
Global average sea level rise | 0.00000000011 | 0.00000000036 | 0.0000000004 | 0.00000000025 | 3.5 mm/year |
Approximate rate of continental drift | 0.0000000013 | 0.0000000042 | 0.0000000045 | 0.0000000028 | 4 cm/year. Varies depending on location. |
Speed of a common snail | 0.001 | 0.003 | 0.004 | 0.002 | 1 millimetre per second |
A brisk walk | 1.7 | 5.5 | 6.1 | 3.8 | |
A typical road cyclist | 4.4 | 14.4 | 16 | 10 | Varies widely by person, terrain, bicycle, effort, weather |
A fast martial arts kick | 7.7 | 25.2 | 27.7 | 17.2 | Fastest kick recorded at 130 milliseconds from floor to target at 1 meter distance. Average velocity speed across kick duration |
Sprint runners | 12.2 | 40 | 43.92 | 27 | Usain Bolt's 100 metres world record. |
Approximate average speed of road race cyclists | 12.5 | 41.0 | 45 | 28 | On flat terrain, will vary |
Typical suburban speed limit in most of the world | 13.8 | 45.3 | 50 | 30 | |
Taipei 101 observatory elevator | 16.7 | 54.8 | 60.6 | 37.6 | 1010 m/min |
Typical rural speed limit | 24.6 | 80.66 | 88.5 | 56 | |
British National Speed Limit (single carriageway) | 26.8 | 88 | 96.56 | 60 | |
Category 1 hurricane | 33 | 108 | 119 | 74 | Minimum sustained speed over one minute |
Average peak speed of a cheetah | 33.53 | 110 | 120.7 | 75 | |
Speed limit on a French autoroute | 36.1 | 118 | 130 | 81 | |
Highest recorded human-powered speed | 37.02 | 121.5 | 133.2 | 82.8 | Sam Whittingham in a recumbent bicycle |
Average speed of Human sneeze | 44.44 | 145.82 | 160 | 99.42 | |
Muzzle velocity of a paintball marker | 90 | 295 | 320 | 200 | |
Cruising speed of a Boeing 747-8 passenger jet | 255 | 836 | 917 | 570 | Mach 0.85 at 35000 ft (10668 m) altitude |
Speed of a .22 caliber Long Rifle bullet | 326.14 | 1070 | 1174.09 | 729.55 | |
The official land speed record | 341.1 | 1119.1 | 1227.98 | 763 | |
The speed of sound in dry air at sea-level pressure and 20 °C | 343 | 1125 | 1235 | 768 | Mach 1 by definition. 20 °C = 293.15 kelvins. |
Muzzle velocity of a 7.62×39mm cartridge | 710 | 2330 | 2600 | 1600 | The 7.62×39mm round is a rifle cartridge of Soviet origin |
Official flight airspeed record for jet engined aircraft | 980 | 3215 | 3530 | 2194 | Lockheed SR-71 Blackbird |
Space Shuttle on re-entry | 7800 | 25600 | 28000 | 17,500 | |
Escape velocity on Earth | 11200 | 36700 | 40000 | 25000 | 11.2 km·s−1 |
Voyager 1 relative velocity to the Sun in 2013 | 17000 | 55800 | 61200 | 38000 | Fastest heliocentric recession speed of any humanmade object. (11 mi/s) |
Average orbital speed of planet Earth around the Sun | 29783 | 97713 | 107218 | 66623 | |
The fastest recorded speed of the Helios probes | 70,220 | 230,381 | 252,792 | 157,078 | Recognized as the fastest speed achieved by a man-made spacecraft, achieved in solar orbit. |
Orbital speed of the Sun relative to the center of the galaxy | 251000 | 823000 | 904000 | 561000 | |
Speed of the Galaxy relative to the CMB | 550000 | 1800000 | 2000000 | 1240000 | |
Speed of light in vacuum (symbol c) | 299792458 | 983571056 | 1079252848 | 670616629 | Exactly 299792458 m/s, by definition of the metre |
Speed | m/s | ft/s | km/h | mph | Notes |
Psychology
According to Jean Piaget, the intuition for the notion of speed in humans precedes that of duration, and is based on the notion of outdistancing. Piaget studied this subject inspired by a question asked to him in 1928 by Albert Einstein: "In what order do children acquire the concepts of time and speed?" Children's early concept of speed is based on "overtaking", taking only temporal and spatial orders into consideration, specifically: "A moving object is judged to be more rapid than another when at a given moment the first object is behind and a moment or so later ahead of the other object."
See also
- Air speed
- List of vehicle speed records
- Typical projectile speeds
- Speedometer
- V speeds
References
![image](https://www.english.nina.az/wikipedia/image/aHR0cHM6Ly93d3cuZW5nbGlzaC5uaW5hLmF6L3dpa2lwZWRpYS9pbWFnZS9hSFIwY0hNNkx5OTFjR3h2WVdRdWQybHJhVzFsWkdsaExtOXlaeTkzYVd0cGNHVmthV0V2WTI5dGJXOXVjeTkwYUhWdFlpODVMems1TDFkcGEzUnBiMjVoY25rdGJHOW5ieTFsYmkxMk1pNXpkbWN2TkRCd2VDMVhhV3QwYVc5dVlYSjVMV3h2WjI4dFpXNHRkakl1YzNabkxuQnVadz09LnBuZw==.png)
![image](https://www.english.nina.az/wikipedia/image/aHR0cHM6Ly93d3cuZW5nbGlzaC5uaW5hLmF6L3dpa2lwZWRpYS9pbWFnZS9hSFIwY0hNNkx5OTFjR3h2WVdRdWQybHJhVzFsWkdsaExtOXlaeTkzYVd0cGNHVmthV0V2WTI5dGJXOXVjeTkwYUhWdFlpOW1MMlpoTDFkcGEybHhkVzkwWlMxc2IyZHZMbk4yWnk4ek5IQjRMVmRwYTJseGRXOTBaUzFzYjJkdkxuTjJaeTV3Ym1jPS5wbmc=.png)
![image](https://www.english.nina.az/wikipedia/image/aHR0cHM6Ly93d3cuZW5nbGlzaC5uaW5hLmF6L3dpa2lwZWRpYS9pbWFnZS9hSFIwY0hNNkx5OTFjR3h2WVdRdWQybHJhVzFsWkdsaExtOXlaeTkzYVd0cGNHVmthV0V2Wlc0dmRHaDFiV0l2TkM4MFlTOURiMjF0YjI1ekxXeHZaMjh1YzNabkx6TXdjSGd0UTI5dGJXOXVjeTFzYjJkdkxuTjJaeTV3Ym1jPS5wbmc=.png)
- "Origin of the speed/velocity terminology". History of Science and Mathematics Stack Exchange. Retrieved 12 June 2023. Introduction of the speed/velocity terminology by Prof. Tait, in 1882.
- Elert, Glenn. "Speed & Velocity". The Physics Hypertextbook. Retrieved 8 June 2017.
- Hewitt 2007, p. 42
- "IEC 60050 - Details for IEV number 113-01-33: "speed"". Electropedia: The World's Online Electrotechnical Vocabulary. Retrieved 2017-06-08.
- Wilson, Edwin Bidwell (1901). Vector analysis: a text-book for the use of students of mathematics and physics, founded upon the lectures of J. Willard Gibbs. Yale bicentennial publications. C. Scribner's Sons. p. 125. hdl:2027/mdp.39015000962285. This is the likely origin of the speed/velocity terminology in vector physics.
- Hewitt 2007, p. 131
- NASA's Goddard Space Flight Center. "Satellite sea level observations". Global Climate Change. NASA. Retrieved 20 April 2022.
- "Improve Kicking Speed for Martial Arts | Get Fast Kicks!". Archived from the original on 2013-11-11. Retrieved 2013-08-14.
- "The Recumbent Bicycle and Human Powered Vehicle Information Center". Archived from the original on 2013-08-11. Retrieved 2013-10-12.
- Darling, David. "Fastest Spacecraft". Retrieved August 19, 2013.
- Jean Piaget, Psychology and Epistemology: Towards a Theory of Knowledge, The Viking Press, pp. 82–83 and pp. 110–112, 1973. SBN 670-00362-x
- Siegler, Robert S.; Richards, D. Dean (1979). "Development of Time, Speed, and Distance Concepts" (PDF). Developmental Psychology. 15 (3): 288–298. doi:10.1037/0012-1649.15.3.288.
- Early Years Education: Histories and Traditions, Volume 1. Taylor & Francis. 2006. p. 164. ISBN 9780415326704.
This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Speed news newspapers books scholar JSTOR July 2016 Learn how and when to remove this message In kinematics the speed commonly referred to as v of an object is the magnitude of the change of its position over time or the magnitude of the change of its position per unit of time it is thus a non negative scalar quantity The average speed of an object in an interval of time is the distance travelled by the object divided by the duration of the interval the instantaneous speed is the limit of the average speed as the duration of the time interval approaches zero Speed is the magnitude of velocity a vector which indicates additionally the direction of motion SpeedSpeed 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 given amount of time while a slow moving object covers a relatively small amount of distance in the same amount of time Common symbolsvSI unitm s m s 1DimensionL T 1 Speed has the dimensions of distance divided by time The SI unit of speed is the metre per second m s but the most common unit of speed in everyday usage is the kilometre per hour km h or in the US and the UK miles per hour mph For air and marine travel the knot is commonly used The fastest possible speed at which energy or information can travel according to special relativity is the speed of light in vacuum c 299792 458 metres per second approximately 1079 000 000 km h or 671000 000 mph Matter cannot quite reach the speed of light as this would require an infinite amount of energy In relativity physics the concept of rapidity replaces the classical idea of speed DefinitionHistorical definition Italian physicist Galileo Galilei is usually credited with being the first to measure speed by considering the distance covered and the time it takes Galileo defined speed as the distance covered per unit of time In equation form that is where v displaystyle v is speed d displaystyle d is distance and t displaystyle t is time A cyclist who covers 30 metres in a time of 2 seconds for example has a speed of 15 metres per second Objects in motion often have variations in speed a car might travel along a street at 50 km h slow to 0 km h and then reach 30 km h Instantaneous speed Speed at some instant or assumed constant during a very short period of time is called instantaneous speed By looking at a speedometer one can read the instantaneous speed of a car at any instant A car travelling at 50 km h generally goes for less than one hour at a constant speed but if it did go at that speed for a full hour it would travel 50 km If the vehicle continued at that speed for half an hour it would cover half that distance 25 km If it continued for only one minute it would cover about 833 m In mathematical terms the instantaneous speed v displaystyle v is defined as the magnitude of the instantaneous velocity v displaystyle boldsymbol v that is the derivative of the position r displaystyle boldsymbol r with respect to time v v r drdt displaystyle v left boldsymbol v right left dot boldsymbol r right left frac d boldsymbol r dt right If s displaystyle s is the length of the path also known as the distance travelled until time t displaystyle t the speed equals the time derivative of s displaystyle s v dsdt displaystyle v frac ds dt 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 displaystyle v s t The average speed over a finite time interval is the total distance travelled divided by the time duration Average speed As an example a bowling ball s speed when first released will be above its average speed and after decelerating because of friction its speed when reaching the pins will be below its average speed Different from instantaneous speed average speed is defined as the total distance covered divided by the time interval For example if a distance of 80 kilometres is driven in 1 hour the average speed is 80 kilometres per hour Likewise if 320 kilometres are travelled in 4 hours the average speed is also 80 kilometres per hour When a distance in kilometres km is divided by a time in hours h the result is in kilometres per hour km h Average speed does not describe the speed variations that may have taken place during shorter time intervals as it is the entire distance covered divided by the total time of travel and so average speed is often quite different from a value of instantaneous speed If the average speed and the time of travel are known the distance travelled can be calculated by rearranging the definition to d v t displaystyle d boldsymbol bar v t Using this equation for an average speed of 80 kilometres per hour on a 4 hour trip the distance covered is found to be 320 kilometres Expressed in graphical language the slope of a tangent line at any point of a distance time graph is the instantaneous speed at this point while the slope of a chord line of the same graph is the average speed during the time interval covered by the chord Average speed of an object is Vav s t Difference between speed and velocity Speed denotes only how fast an object is moving whereas velocity describes both how fast and in which direction the object is moving If a car is said to travel at 60 km h its speed has been specified However if the car is said to move at 60 km h to the north its velocity has now been specified The big difference can be discerned when considering movement around a circle When something moves in a circular path and returns to its starting point its average velocity is zero but its average speed is found by dividing the circumference of the circle by the time taken to move around the circle This is because the average velocity is calculated by considering only the displacement between the starting and end points whereas the average speed considers only the total distance travelled Tangential speed This section is an excerpt from Tangential speed edit Angular speed and tangential speed on a discTangential speed is the speed of an object undergoing circular motion i e moving along a circular path A point on the outside edge of a merry go round or turntable travels a greater distance in one complete rotation than a point nearer the center Travelling a greater distance in the same time means a greater speed and so linear speed is greater on the outer edge of a rotating object than it is closer to the axis This speed along a circular path is known as tangential speed because the direction of motion is tangent to the circumference of the circle For circular motion the terms linear speed and tangential speed are used interchangeably and both use units of m s km h and others UnitsUnits of speed include metres per second symbol m s 1 or m s the SI derived unit kilometres per hour symbol km h miles per hour symbol mi h or mph knots nautical miles per hour symbol kn or kt feet per second symbol fps or ft s Mach number dimensionless speed divided by the speed of sound in natural units dimensionless speed divided by the speed of light in vacuum symbol c 299792 458 m s Conversions between common units of speed m s km h mph mi h knot fps ft s 1 m s 1 3 600000 2 236936 1 943844 3 280840 1 km h 0 277778 1 0 621371 0 539957 0 911344 1 mph mi h 0 44704 1 609344 1 0 868976 1 466667 1 knot 0 514444 1 852 1 150779 1 1 687810 1 fps ft s 0 3048 1 09728 0 681818 0 592484 1 approximate values Examples of different speedsThis section needs additional citations for verification Please help improve this article by adding citations to reliable sources in this section Unsourced material may be challenged and removed May 2013 Learn how and when to remove this message This section may contain excessive or irrelevant examples Please help improve the article by adding descriptive text and removing less pertinent examples May 2014 Speed m s ft s km h mph NotesGlobal average sea level rise 0 000000 000 11 0 000000 000 36 0 000000 0004 0 000000 000 25 3 5 mm yearApproximate rate of continental drift 0 000000 0013 0 000000 0042 0 000000 0045 0 000000 0028 4 cm year Varies depending on location Speed of a common snail 0 001 0 003 0 004 0 002 1 millimetre per secondA brisk walk 1 7 5 5 6 1 3 8A typical road cyclist 4 4 14 4 16 10 Varies widely by person terrain bicycle effort weatherA fast martial arts kick 7 7 25 2 27 7 17 2 Fastest kick recorded at 130 milliseconds from floor to target at 1 meter distance Average velocity speed across kick durationSprint runners 12 2 40 43 92 27 Usain Bolt s 100 metres world record Approximate average speed of road race cyclists 12 5 41 0 45 28 On flat terrain will varyTypical suburban speed limit in most of the world 13 8 45 3 50 30Taipei 101 observatory elevator 16 7 54 8 60 6 37 6 1010 m minTypical rural speed limit 24 6 80 66 88 5 56British National Speed Limit single carriageway 26 8 88 96 56 60Category 1 hurricane 33 108 119 74 Minimum sustained speed over one minuteAverage peak speed of a cheetah 33 53 110 120 7 75Speed limit on a French autoroute 36 1 118 130 81Highest recorded human powered speed 37 02 121 5 133 2 82 8 Sam Whittingham in a recumbent bicycleAverage speed of Human sneeze 44 44 145 82 160 99 42Muzzle velocity of a paintball marker 90 295 320 200Cruising speed of a Boeing 747 8 passenger jet 255 836 917 570 Mach 0 85 at 35000 ft 10668 m altitudeSpeed of a 22 caliber Long Rifle bullet 326 14 1070 1174 09 729 55The official land speed record 341 1 1119 1 1227 98 763The speed of sound in dry air at sea level pressure and 20 C 343 1125 1235 768 Mach 1 by definition 20 C 293 15 kelvins Muzzle velocity of a 7 62 39mm cartridge 710 2330 2600 1600 The 7 62 39mm round is a rifle cartridge of Soviet originOfficial flight airspeed record for jet engined aircraft 980 3215 3530 2194 Lockheed SR 71 BlackbirdSpace Shuttle on re entry 7800 25600 28000 17 500Escape velocity on Earth 11200 36700 40000 25000 11 2 km s 1Voyager 1 relative velocity to the Sun in 2013 17000 55800 61200 38000 Fastest heliocentric recession speed of any humanmade object 11 mi s Average orbital speed of planet Earth around the Sun 29783 97713 107218 66623The fastest recorded speed of the Helios probes 70 220 230 381 252 792 157 078 Recognized as the fastest speed achieved by a man made spacecraft achieved in solar orbit Orbital speed of the Sun relative to the center of the galaxy 251000 823000 904000 561000Speed of the Galaxy relative to the CMB 550000 1800 000 2000 000 1240 000Speed of light in vacuum symbol c 299792 458 983571 056 1079 252 848 670616 629 Exactly 299792 458 m s by definition of the metreSpeed m s ft s km h mph NotesPsychologyAccording to Jean Piaget the intuition for the notion of speed in humans precedes that of duration and is based on the notion of outdistancing Piaget studied this subject inspired by a question asked to him in 1928 by Albert Einstein In what order do children acquire the concepts of time and speed Children s early concept of speed is based on overtaking taking only temporal and spatial orders into consideration specifically A moving object is judged to be more rapid than another when at a given moment the first object is behind and a moment or so later ahead of the other object See alsoAir speed List of vehicle speed records Typical projectile speeds Speedometer V speedsReferencesLook up speed or swiftness in Wiktionary the free dictionary Wikiquote has quotations related to Speed Wikimedia Commons has media related to Speed Origin of the speed velocity terminology History of Science and Mathematics Stack Exchange Retrieved 12 June 2023 Introduction of the speed velocity terminology by Prof Tait in 1882 Elert Glenn Speed amp Velocity The Physics Hypertextbook Retrieved 8 June 2017 Hewitt 2007 p 42 IEC 60050 Details for IEV number 113 01 33 speed Electropedia The World s Online Electrotechnical Vocabulary Retrieved 2017 06 08 Wilson Edwin Bidwell 1901 Vector analysis a text book for the use of students of mathematics and physics founded upon the lectures of J Willard Gibbs Yale bicentennial publications C Scribner s Sons p 125 hdl 2027 mdp 39015000962285 This is the likely origin of the speed velocity terminology in vector physics Hewitt 2007 p 131 NASA s Goddard Space Flight Center Satellite sea level observations Global Climate Change NASA Retrieved 20 April 2022 Improve Kicking Speed for Martial Arts Get Fast Kicks Archived from the original on 2013 11 11 Retrieved 2013 08 14 The Recumbent Bicycle and Human Powered Vehicle Information Center Archived from the original on 2013 08 11 Retrieved 2013 10 12 Darling David Fastest Spacecraft Retrieved August 19 2013 Jean Piaget Psychology and Epistemology Towards a Theory of Knowledge The Viking Press pp 82 83 and pp 110 112 1973 SBN 670 00362 x Siegler Robert S Richards D Dean 1979 Development of Time Speed and Distance Concepts PDF Developmental Psychology 15 3 288 298 doi 10 1037 0012 1649 15 3 288 Early Years Education Histories and Traditions Volume 1 Taylor amp Francis 2006 p 164 ISBN 9780415326704 Hewitt P G 2007 Conceptual Physics Pearson Education ISBN 978 81 317 1553 6 Retrieved 2023 07 20 Richard P Feynman Robert B Leighton Matthew Sands The Feynman Lectures on Physics Volume I Section 8 2 Addison Wesley Reading Massachusetts 1963 ISBN 0 201 02116 1