The Stunt
Jackass is well known for its crazy, outrageous,
dangerous, and stupid stunts. For example, one of
the stunts, Toro Totter, was performed in the movie
Jackass Number 2. Four of the members from the show
participated for this daredevil stunt. Two of the
guys positioned on each teeter toter using it to
maneuver the bull. The last man standing on the
teeter totter is the declared the winner. You had to
have bull balls or a thick skull for this one.
Physics
A teeter totter has a pivot point and a center of
mass in the middle of the board. As stated in
Newton’s Third Law for every action, there must be
an equal and opposite reaction force. Whenever an
object is balanced on a pivot point, the turning
forces on each side must be in equilibrium. Thus, on
one side of the pivot, the force will move in a
counterclockwise motion. On the opposite side, the
force will move in a clockwise motion. The board
will be perfectly balanced on the pivot point when
the object equals the same weight and distance of
the object of the other side. Otherwise, if you were
to replace the one of the previous objects with a
heavier object on one side and position it closer to
the pivot point, perfect balance can still be
attained. The Reason being is the center of the
pivot can hold more weight than both of the other
sides as stated earlier by Newton's third law. For
example, if a child was sitting further on the end
of a teeter totter, and a heavier adult was to sit
on the other side.The adult would have to sit closer
to the pivot point compared to the child to gain
perfect balance, as depicted in the image below.
In other words, the
board moves or rotates based upon if
the torque is greater on one side
then the other. Therefore, the board
rotates in the direction with the
highest amount of torque. The board
will have a flat and perfect balance
when in equilibrium. The torque on
both sides equal the same exact
value..
Formulas
The Formulas used for this are:
1. Force of Gravity (Fg): Fg= m * g
2. Force (F): F = m * a
3. Torque (𝞃):
𝞃
= Fg
* d or 𝞃
= F * d
4. Total Force (Ftotal):
Ftotal = F1
+ F2
= 0
6. F1a
* d1a
+ F1b
* d1b =F2a
* d2a
+ F2b
* d2b
7. Torque Equilibrium:𝞃1total = 𝞃2total
Symbols
d = distance from pivot point / center of
mass.
m = mass of object / person
g = (9.81 m / s^2) acceleration of gravity on earth
a = acceleration
F1
= Force on side 1
F2
= Force on side 2
D1
= Distance on side 1
D2
= Distance on
side 2
