How do I find average velocity over a given time interval?

1 Answer
May 17, 2015

Average velocity = total distance / total time

Example:
I travel from Rotterdam to Amsterdam (100 km) with an average speed of 80 km/h and return with an average speed of 120 km/h.

Then my average verlocity is NOT 100 km/h, but:

Time for the trip out: #(100km)/(80km//h)=1.25h#

Time for the trip back: #(100km)/(120km//h)~~0.83h#

Total time: #1.25+0.83=2.08h# over #200 km#

Average velocity: #200/2.08=96.0km//h#

This may be counter-intuitive, but remember you spend more time in the slow mode than in the fast mode.