Question

During World War 2, there were some cases where the crew fell out of burning aircraft without a parachute and survived the fall. Assume that the crew member reached a constant terminal speed of 128.3 km/hr prior to hitting a stack of loose hay. If the crew member can survive an acceleration of 34.0 g, where g is the gravitational constant, and assuming uniform acceleration, how high a stack of hay is required for the crew member to survive the fall?

I'm stuck on which eqaution I need to use for this.

Answer 1

constant acceleration means
v = Vo + a t
We know Vo (convert it from km/hr to meters/second)
We know a = -34(9.8)
set v = 0, we stopped and solve for t, time spent deaccelerating in the hay
then
x = Xo + Vo t + (1/2) a t^2
here x is unkown
call Xo = 0 start of deacceleration
we know Vo and t and a from above
solve for x, distance through hay