Question

How do I convert m/s to km/h? Give an example.

Answer 1

Hint: The metre per second (m/s) is a SI unit of speed (scalar quantity) and velocity (vector quantity (which has direction and magnitude) equal to the speed of a body covering one metre in one second. The kilometre per hour (SI symbol: km/h) is a speed unit that measures the distance travelled in one hour.

Complete answer:
A kilometer per hour (km/h) is a unit of speed that measures how far an object travels in one hour. The base length unit in the SI system of units is the kilometer, which is defined as one thousand meters. The kilometer per hour is usually expressed as a ratio, such as km/h. It does, however, appear as an abbreviation (kmph, kph) on labels and road signs.

The SI system of units defines meters per second [m/s] as a unit of speed. It calculates how many meters an object travels in a second. The SI system's base unit of length is the metre [m]. It was originally intended to be 1/10,000,000 of the distance between the equator and the North Pole along the earth's meridian. It is now defined as the distance travelled by the light in vacuum in $\dfrac{1}{{299792458}}$ second.

To convert m/sec into km/hr: Multiply speed in m/s with 3600.Divide the results by 1000.The result is the speed in kilometers per hour.
Example: Convert 20 m/sec into km/hr
Step 1: Multiply 20 by 18
We have $20 \times 18 = 360$
Step 2: Divide 360 by 5
We have $\dfrac{{360}}{5} = 72$
Therefore, $20\,\dfrac{m}{s} = 72\,\dfrac{{km}}{h}$
And hence, $1\,\dfrac{m}{s} = 3.6\,\dfrac{{km}}{h}$

Note: The term "speed" is defined as the rate at which an object's position changes in any direction. Speed is defined as the ratio of distance travelled to the time it took to travel that distance. Because speed has only one direction and no magnitude, it is a scalar quantity.