If an airplane is traveling at 900 km/hr and slows to 450km/hr in 2.5 minutes. What is the plane's acceleration?

2 answers

Acceleration = [ (final velocity) - (initial velocity) ] / (time elapsed)

Make sure you have "like" units. In this case, convert the 2.5 min to hrs and plug everything into the equaiton.
a = [450km/hr - 900 km/hr]/2.5 minutes
a = [-450km/hr]/2.5 minutes
a= [-450km/hr]/0.416 hrs
a = -10817.31km/hr2

is that correct?