Question

An air craft has a take off speed V = 180 km/h and the take off point is at a distance l = 250 m from the
start. Just before take off a serious snag in the engine is detected and the air craft fails to take off
There was a wall at a distance d = 270 m ahead of the take off point. The pilot applies brake which
produces as much retardation as the acceleration of the craft and succeeds in avoiding the crash on the
wall. What is the reaction time of the pilot? Find your Answer in form of sec. Find the value of x.
10
(Reaction time is define as time interval between observation and it's reaction.)​

Answer 1

Answer:

t=10.80 sec

Explanation:

d = 270 m = Required stopping distance.

Vo = 180 km/h = 180,000/3600 = 50 m/s. = Initial velocity before take-off.

V^2 = Vo^2 + 2×a×d.

0 = (50)^2 + 2×a×270

-540×a = 2500

a = -4.63m/s^2.

now  

V = Vo + a×t.

0 = 50 - 4.63t

t = 50/4.63= 10.80 sec