Question

a 727 jet needs to attain a speed of 200 mph to take off. if it can accelerate from 0 to 200 mph in 30 seconds, how long must the runway be? (assume constant acceleration)

Answer 1

v-u=at
v=200mph =89.408 m/s
u=0
t=30
a=?
v-u=at
89.408=a*30
a=2.9802m/s^2
now
the runway's length be s
v^2-u^2=2as
89.408^2=2*2.9802*s
s=89.408^2/(2*2.9802)

s=1341.15 meters
in miles 0.833