"Last year, a sample of the ApNano material was subjected to tests in which a steel projectile traveling at a speed of up to 1.5 kilometers per second slammed into the material.
Executives said the impact was the equivalent to dropping four diesel locomotives onto an area the size of a human fingernail."
This means nothing if they don't say what height the locomotors would have been dropped from. Let's make a quick calculation shall we?
Kinetic Energy KE=mv² , where m is the mass and v is the velocity.
Let's assume the projectile weighs 50g. So the round had a KE of 0.05kg x (1500 m/s²)=112500 J
The 4 locomotors must have the same KE. Let's assume they weigh 200 tons altogether: then their velocity v=square root of (112500 J / 200,000kg)= 0.75 m/s
So now we want to find the height they are dropped from:
h= 1/2 v dt , where dt is a difference in time.
dt can be calculated from dt= v/g , where g=9.8 m/s² is the earth's gravitational acceleration.
h= 1/2 v²/g= 0.5(0.75 m/s)²/9.8 m/s²= 0.029 m.
So the impact of the bullet is equivalent to the impact of 4 locomotors dropped from a height of a few centimeters....Assuming the locomotors are as big as a fingernail