The roof of the Sears Tower is at an elevation of 1451 ft (442.3 m), so, how fast would a person be travelling when he or she hit the concrete below? What would be the force of the impact? Would the impact (presuming at 150 lb male) break the concrete? I suck at physics so anybody willing to indulge me in the physics of this would be my new best friend. Thanks!
2006-12-15 06:15:15 · 3 answers · asked by ryguillian 2 in Science & Mathematics ➔ Physics
nobody really answered your question to my satisfaction So I will.
Number one principal is called "Terminal Velocity" It is the velocity at which a falling object stops accelerating under gravity and falls at a constant speed. For a person falling under gravity terminal velocity is approximatly 120 mph. Or about the same as falling from 500 feet. Any heights beyond that are meaning less. So your question would be the same if a person fell from 500 feet, or 50,000 feet.
Now Aerodynamics does have some say in how fast a person is falling depending on their orientation in the air. If they were in a dive as apposed to if they were in what skydivers would call an arch. The less aerodynamic their form the less resistance they are going to have from air particles on their body.
As far as the impact goes, you can calculate it by the equation F=mv (force =mass times velocity) we know the velocity from terminal velocity... we know the mass (you need to turn your 150 lb dude into mass) so you can multiply them and get the force.
Now to see if it would break concrete is a bit more tricky, but I think if you did some research into concrete shattering pressures you could probably figure that out.
2006-12-16 05:33:44 · answer #1 · answered by travis R 4 · 0⤊ 0⤋
I'm not exactly sure of the math, but I do believe that the individual would reach his or her terminal velocity (the point at which wind Resistance equals gravitational pull) and would not fall any faster from a much shorter fall. Terminal velocity would be the best focus for you. However, I do know that a falling human from a plane would probably crush into mush before he or she broke the crete. skin and bones is softer than rock and sand.
2006-12-15 14:31:44 · answer #2 · answered by stevenhendon 4 · 1⤊ 0⤋
Final velocity Vf=sqrt(2*g*h)
Final energy Ef= 0.5*m*Vf^2
That is in the vacuum
2006-12-15 15:18:33 · answer #3 · answered by Anonymous · 0⤊ 0⤋