An aircraft lands and brakes, slowing from 250 m/s to 5 m/s in 30 secs. What is its acceleration?

2 Answers
May 26, 2018

#8.17" m s"^-2#

Explanation:

#a=(v-u)/t# where

#a# is acceleration
#v# is final velocity
#u# is intial velocity
#t# is time.

#a=(5-250)/30#
#=-245/30#
#=-49/6" m s"^-2#
#~~8.17" m s"^-2#

May 26, 2018

#-8.16# #ms^-2#

Explanation:

To solve this, we use the formula

#color(blue)(a=(v-u)/t#

Where, #a# is the acceleration, #v# is the final and #u# the initial velocities.And, #t# is the time taken

So, here, initial velocity is #250m/s# and final velocity is #5m/s# and the time taken is #30s#

#rarra=(5-250)/30# #ms^-2#

#rarra=-245/30ms^-2#

#rarra=-49/6ms^-2#

#color(green)(rArra~~-8.16# #color(green)(ms^-2#

Note: here the value is negative, so the plane is decelerating(opposite of accelerating). So, this is known as deceleration.

Hope that helps...#phi#