Time speed and distance is very important topic for various entrance examinations. The entire topic revolves around only one concept i.e. \[\rm{Speed} =\frac{{{\rm{Distance}}}}{{{\rm{Time}}}}\]

In this topic we will limit our discussion only to those cases where speed is constant.

UNITS USED

The following conversions will be useful 

1 hour = 60 minutes = 3600 seconds

1 km = 1000 m

Approximately 1 mile = \(\frac{8}{5}\) km 

1 yard = 3 feet and 1 foot = 12 inches 

The commonly used units of speed are km/hr or m/s. The conversion factors of these units are given below:

Speeds in m/s =\(\frac{5}{{18}} \times\) speed in km/hr

Speed in km/hr =\(\frac{{18}}{5} \times\) speed in m/s

For example, a speed of 72 km/hr is equivalent to \(\frac{5}{{18}} \times 72\) = 20 m/s

Or speed of 40 m/s = \(\frac{{18}}{5} \times 40\) = 144 km/hr

A car is moving with a speed of 72 km/hr, in how many minutes it can cover a distance of 600 m.