# Centrifugal force and those Mike Rowe Ford Truck Commercials

1. Mar 27, 2008

### bitrex

Hello everyone,

It's been a long time since I've taken a physics course, but recently I've become interested again and am studying some classical mechanics in my spare time. I was thinking the other night about that computer generated Ford commercial where the truck is spun on a rotating arm by its tow hooks. From the ad I'd guess the length of the arm is about 50 meters, rotating at about 1 Hz, and I know the curb weight of a Ford F-150 is around 1800kg. Using

$$F=-m\omega^2r$$

I get a centrifugal force of over 3.5 million newtons! Now supposedly these commercials are based on "actual lab tests", so I assume that somewhere sometime engineers have calculated the actual amount of combined force that can be applied to the tow hooks before they shear. Now obviously most car ads are BS, but is this one total BS or could those tow hooks really stand up to that kind of force?

2. Mar 27, 2008

### belliott4488

Well, I haven't seen the ad, but are you sure your estimates are right? 50 m is about half a football field - is that really right? Also, 1 Hz mean one second for that huge arm to complete a full 360 degree rotation - again, right?

That translates to a linear speed of around 1131 km/hr for the truck ... that seems kind of unlikely to me ....

3. Mar 27, 2008

### Staff: Mentor

4. Mar 27, 2008

### bitrex

Well, I did some looking for the commercial, and I found a Youtube video of it. My assumption about the length of the rotating arm was way off. It looks like the actual length of the arm is about 1/25th of what I thought it was for the calculation, and the rate of rotation is slower. I never was very good at estimating. Anyway, the joke is on me, as I also found a "making of" video of the commercial in which it shows a real setup and real truck being spun. I had assumed it was CGI. Here:

It says the truck was subjected to 6 Gs. I suppose if the arm were actually 50 meters and mounted vertically it might be a good way of sending F-150s into space...

Last edited by a moderator: Sep 25, 2014