The distance covered by a body in unit time is called speed. For mentioning speed we do not require any direction, so it is scalar quantity.
Speed (V) =
Total distance covered (S)
Total Time (t)
TYPES OF SPEED
If a moving body covers equal distance in equal intervals of time then its speed is called uniform speed.
If a moving body does not covers equal distance in equal intervals of time its speed is called variable speed
A body is said to have variable speed if is speed is changing continuously.
3- AVERAGE SPEED:
If the speed of the body is obtained by dividing the total distance by the time taken, then the speed is said to be average speed.
Average speed is symbolically represented by V. if a body covers a distance “S” in time “t” then its average speed V is given by the equation.
Speed for a very short interval of time is called instantaneous speed.
- OR -
Distance covered by a body in short interval of time is called instantaneous speed.
UNIT OF SPEED:
The unit of speed in various systems of units are:
C.G.S System: cm/s or cm s-1
M.K.S System: m/s or ms-1
F.P.S System: ft/s or ft.s-1