Physics: Unit of Speed

Introduction

Speed simply refers to the rate at which an object travels a certain distance in a given amount of time. Speed can also be defined as how quickly an item moves to traverse a distance. Speed is a scalar quantity, meaning it has just magnitude. What is the difference between two identical objects travelling at different speeds? Their only difference is that one travels quicker (the faster one) and will travel further in the same period than the slower one. This also indicates that the faster-travelling thing will arrive at its destination faster than the slower-moving object.

What Is Speed?

The rate of change of position of an object travelling in any direction is defined as speed. The famous Italian astronomer Galileo Galilei was the first to determine speed by measuring distance over time.

Speed is defined as the ratio of an object’s distance travelled to the time it took to travel that distance. It is a scalar quantity with no related direction and simply magnitude. Speed is the rate at which an item travels to traverse a given distance. A negative value for speed is not possible. It is represented by the symbol v and is measured in metres per second (m/s).

Vehicles’ speeds are measured using speedometers. Odometers measure how far a vehicle has driven. A graph, such as the distance-time graph, can aid in determining speed. It assists in determining the speed of an object.

What is the SI Unit of Speed?

SI Units are the world’s standard units of measurement that are used to minimise confusion. The International System of Units defines SI units for any physical quantity (SI).

Metres per Second (m/s) is the SI unit of speed. This standard measure of speed represents the distance an object may move in one second. For example, if an object moves 10 metres in a second, its speed is 10 metres per second.

The SI unit of speed is derived from the standard units of time and distance (metres) (seconds). It may be explained as follows:

Unit of Speed = Unit of Distance/Unit of Time

Unit of Speed = m/s

Other Units of Speed

Aside from the SI unit, speed may be measured in a variety of different units. In certain cases, such as assessing a vehicle’s speed, it is more practical to use hours rather than seconds. Vehicle speeds are thus measured in kilometres per hour (kmph) or miles per hour.

• Kilometres per hour (symbol km/h); metres per second (SI derived unit, m/s).
• Miles per hour (mi/h or mph) is a unit of measurement used to indicate a vehicle’s speed.
• Knots (nautical miles per hour, symbolised by sign kn or kt)
• Feet per second (symbol fps or ft/s) is a speed measurement unit.

The different speed-measuring systems are as follows:

CGS Unit of Speed: In the CGS unit system, length is measured in centimetres and time in seconds. As a result, the unit of speed is centimetres per second or cm/s.

FPS Speed Unit: FPS Speed Units are imperial units. In this context, length is measured in feet and time is measured in seconds. As a result, the unit of speed is stated as a foot per second, or ft/s.

Speeds of Earth, Air, and Light

• The average orbital speed of Earth is roughly 30 km/s.
• At the equator, the Earth’s surface travels at a pace of around 460 m/s, which equates to about 1,000 miles per hour.
• The speed of light in a vacuum is roughly 299,792 kilometres per second (186,282 miles per second).
• The speed of sound in the air is roughly 343 m/s, or 767 mph, or 1235 km/h.

Recommended Articles:

Unit of Temperature and Its Types of Units
Unit of Torque: Definition, SI and Other Units
What are the Units of Vibration?
Unit of Voltage: Definition, Formula and SI Unit
Unit of Wavelength – Definition, Types, Symbol and Units