: He squinted at the cable. It looked like 2-centimeter thick steel wire rope. From memory, the breaking strength of a 2cm steel cable was somewhere around
The foreman looked at the frantic physicist, then at the envelope covered in scratched-out numbers and coffee stains. He looked up at the girder, which gave another ominous groan. He didn't ask for a peer-reviewed study; he grabbed his radio. Back-of-the-Envelope Physics
He looked closer. It wasn't the cable. It was the attachment point —the bolt assembly on the girder itself. It was smaller, maybe 5 centimeters across. He quickly calculated the shear stress on a single high-strength bolt. : He squinted at the cable
: The wind was gusting. The girder was oscillating about 5 degrees from the vertical. Leo scribbled a quick triangle. The centripetal force at the bottom of the swing would add to the tension. Estimate : At that height and arc, the velocity was maybe He looked up at the girder, which gave another ominous groan
Leo shrugged, finally feeling the adrenaline fade. "The math is simple. It's the envelope that's hard to find."
"Stop the winch!" Leo screamed, thrusting the envelope into the man's hands.