Velocity n Speed

Velocity and Speed



* Speed is equal to distance traveled divided by time taken
* Velocity is equal to displacement divided by time taken.
* Velocity is speed with a direction. If we calculate an object velocity, we have to think about its direction too.


Calculating the speed

The way to calculating speed is
v = d : t
or
d = v x t

* The unit of distance in SI is meter, and the Unit of time is second; therefore the unit of speed is meter per second (m / s).
* The difference between velocity & speed is only in direction. The unit of velocity is same as speed, m / s



The Question of Speed

1. An athlete made his world record of 10 km within 20 minutes. What was his speed?

Solution:
Known:
Distance, d = 10 km = 10.000 m
Time,
t = 20 minutes = 1200
Asked:
speed, v = ? use equation v = d / t
Result:
v = d / t = (10.000 m) / (1200 s) = 8.33 m / s