The motion of an airplane taking off on a straight runway can be described by the equation v = as +30 where s is distance in metres and a is a constant. (i) For taking off at Heathrow, the coefficient a = 0.1 per second, calculate the acceleration of the aircraft when the distance s = 400 m. (ii) If the acceleration a should be 8.5 m/s? at s = 400 m at Gatwick, calculate what the value of the coefficient a should be in order for the plane to be able to take off successfully.

The motion of an airplane taking off on a straight runway can be described by the equation v = as +30 where s is distance in metres and a is a constant. (i) For taking off at Heathrow, the coefficient a = 0.1 per second, calculate the acceleration of the aircraft when the distance s = 400 m. (ii) If the acceleration a should be 8.5 m/s? at s = 400 m at Gatwick, calculate what the value of the coefficient a should be in order for the plane to be able to take off successfully.