Question

Paleontologists estimate that if a Tyrannosaurus rex were to trip and fall, it would have experienced a force of approximately 260,000 N acting on its torso when it hit the ground.

Question 1
Assuming the torso has a mass of 3800 kg , find the magnitude of the torso's upward acceleration as it comes to rest. (For comparison, humans lose consciousness with an acceleration of about 7g .)

Question 2
Assuming the torso is in free fall for a distance of 1.21 m as it falls to the ground, how much time is required for the torso to come to rest once it contacts the ground?

Answer 1

a.
Use F=mA
F=260,000 N
m=3800kg
acceleration A=?

b. v²-v0²=2aS
Initial velocity, v0=0 m/s
acceleration due to gravity, g = -9.8 m/s/s
final velocity (end of free fall), v
distance fallen, S = 1.21 m
what is v?

The moment rex is in contact with the ground, decelleration starts.
Using the upward acceleration from part a., we can apply the formula
v2=v+At
v2=final velocity=0
v=velocity at impact, calculated above.
A=upward acceleration calculated from part a.
t can be isolated and calculated.