Trying to work out the force on Massa when the spring and his helmet met.

According to an article on f1live the spring weighed 800g and he was moving at 275 kph. I am not sure if this is the best formula to use, Force = Mass * Acceleration
800g * 275 k/h = 220000 grams of force or 220 KG striking his head.

I believe Steve M said Sunday it was like 1600 lbs of force striking the helmet.

I am hoping that someone could explain, am I using the correct formula, maybe why Steve said such a high number.

Thanks in advance for your help.

Velocity is not the same thing as acceleration.

You (or Steve Matchett) can't really estimate the force involved (too many unknown variables), but you can estimate the kinetic energy. It's a lot, about the same as a shot from a large gun.

jim515 - 28 July 2009 10:51 AM

Trying to work out the force on Massa when the spring and his helmet met.

According to an article on f1live the spring weighed 800g and he was moving at 275 kph. I am not sure if this is the best formula to use, Force = Mass * Acceleration
800g * 275 k/h = 220000 grams of force or 220 KG striking his head.

I believe Steve M said Sunday it was like 1600 lbs of force striking the helmet.

I am hoping that someone could explain, am I using the correct formula, maybe why Steve said such a high number.

Thanks in advance for your help.

The spring was traveling at a velocity as it decelerated from Barrichello's car. Therefore, you would have to add Massa's speed to the Spring's speed to come up with the final impact speed.

It would be complicated to come up with the exact impact force. But the estimate is already really high from the simple known variables.

Well...you can compare kinetic energy of a bullet with the kinenetic energy of spring.

The spring is
1/2 * 0.8 [kg] * (76.38 [m/s]) ^2 = 2334.1 Joules

Bullet is

1/2 * .008 [kg] * ( 358 [m/s] ) ^ 2 = 512.6 Joules

ouch!

more kinetic energy examples:
http://en.wikipedia.org/wiki/Projectile#Typical_projectile_speeds
(need the mass of object to compare)

Ok, lets first find out how fast the spring was traveling when it hit Massa. The easiest way to do this is estimate the distance between the video frames of the spring. In the videos shown, it appears to travel from just in front of the nose of the car to Massa's hands, which looks to be about 4.5 feet. And knowing that the video is shot in 30 frames/second, we can calculate that the spring was traveling 4.5ft/(1/30)second, or 135ft/s which is 92.045MPH and 147.272 KPH. Although this seems like a low number, you have to remember that the spring was still traveling down the track at a relatively high speed in the same direction along with Massa being on a cool down lap so he wasn't at full speed.

So using this equation were M = Mass (Kg) And V = Velocity (M/S), and converting 147.272KPH to Meters/Second (40.909M/S)



We get an Equation of

Ek = (1/2) * (.8Kg) * (40.909M/S)^2 = 669.419 Joules

Although 669.419 Joules seems like a relatively useless number, to put it in perspective here is a list of the Muzzle energy of rifles/handgun rounds in joules to compare to. As you can see the energy caused by the impact of the spring is greater then a .45 Colt round, but of course the surface area of the two are drastically different, thus more of a blunt force from the spring.


Video used for distance measurement

http://www.youtube.com/watch?v=B6Ybv0A-tV0

Here's a good article.
http://www.f1fanatic.co.uk/2009/07/28/how-hard-was-massa-hit/

Thanks to everyone for posting the math about this. Glad Massa is going to be fine.

That linked article put it pretty clearly when it estimated 4 times the energy of a Barry Bonds bat hitting you in the head. Incredible.

The spring was traveling at a velocity as it decelerated from Barrichello's car. Therefore, you would have to add Massa's speed to the Spring's speed to come up with the final impact speed.

It would be complicated to come up with the exact impact force. But the estimate is already really high from the simple known variables.



brianI
Simulation prêt

brianiron - 21 October 2009 12:05 AM

The spring was traveling at a velocity as it decelerated from Barrichello's car. Therefore, you would have to add Massa's speed to the Spring's speed to come up with the final impact speed.

I think you mean subtract the spring's speed from Massa's speed; they were both traveling in the same direction, Massa at a greater speed.