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Cow tipping is a pastime allegedly common in rural areas, in which participants sneak up on an upright sleeping cow and then push it over for amusement. Some variants of this urban legend state that the cow is then unable to get up.

Fact or urban legend?

Based on the cow's weight and body structure, and the potential force that could be exerted make the tipping by pushing physically impossible for a single person. However it could potentially be done by two people. The amount of force and feasibility of tipping would also be highly dependent upon the stance of cow at the moment. Adding to this problem is the fact that most cows sleep lying down.

Is cow-tipping mathematically possible?

How many people are needed to tip a cow?

Cow Tipping Formula:

Averages:

   Average mass of a cow = 1400 lbs (Source: Local Farmers)

   Average pushing force of a human (Source: UNL Football Asst.) 

   Average height of human = 6' 
   Average height of human arms = 5' 
   Average horizontal push force of a human = 300 lbs 

Force and Friction:

   Force of Friction = 1400(.45) = 630 lbs (Assumed) 

(Cow will not slide)

   MA = 300(5) - 1400(1.25) = -250

(Counter-clockwise)

Results

After taken a counter-clockwise moment about the point A, it is shown that the weight of the cow creates more turning force than the human pushing force. The force of friction is not important here because it's force vector runs through the point A. The normal force can also be left out because before the pushing force is included the normal force of 1400 lbs. is divided in two with equal forces pushing at the center of both legs upward. This means that the cow is balanced. The normal force, though, moves to point A when the pushing force is applied, meaning that this force cancels out. The calculated moment comes out to negative 250 foot pounds, which can also be thought of as 250 foot pounds of force keeping the cows feet pressed against the ground. According to these calculations, it is impossible for an average person to tip an average cow by them self.

Try 2 people:

 Pushing force = 2 x 300 = 600 lbs 
 MA = 600(5) - 1400(1.25) = 1250 

(Counter-clockwise)

Conclusion Nr.1

Since it has already been shown that one person cannot tip a cow by them self, we can figure out just how many people would have to be pushing in order to complete the prank. By adding the second person, the amount of human pushing force is doubled to 600 pounds, still less than the force of friction. When the moment is calculated about A again, we find that there is now a positive 1250 foot pounds of force turning the cow about its feet and therefore tipping the cow on it's side. According to these numbers, cow tipping is possible when two people are in on the prank.

Conclusion Nr.2

You can go through all the math and physics or you can look at this urban myth a bit differently. Since cows do not sleep standing (like horses do) and cow tipping is a night time activity while the cow is asleep, it just is not possible to tip an "already tipped" cow.

References

1. UNL College of Engineering and Mechanics. "The Statics of Cow Tipping". University of Nebraska-Lincoln. Retrieved 2006-10-28.
2. Malvern, Jack. "Cow-tipping myth hasn't got a leg to stand on". Times Online. Retrieved 2006-10-28.
3. "The Mechanics of Cow Tipping" (PDF). University of British Columbia. 2003-04-09. Archived from the original (PDF) on 2005-03-20.

See also

• Steer wrestling in which a running steer is "tipped".
• Geier Hitch, whereby a running bull is "steered"
• Toilet tipping

External links

• The Most Urban of All Urban Legends
• Adventures in cow tipping - Fiction!
• The Times article on Cow Tipping by Jack Malvern
• The Register article debunking the myth of cow tipping while drunk by Lester Haines
• Straight Dope article - Discusses whether it is possible.
• The Statistics of Cow Tipping - A Page of Statistical & Somewhat Humorous Research.

• Cattle
• Urban legends
• Practical jokes