Block 4

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Kung Fu Hustle

• Block 4
• Mr. Taylor

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Introduction

• Kung Fu Hustle is the typical kung fu/action
  movie, with little plot but a lot of cool fights
• The story takes place in 1940s China and
  revolves around a wannabe gangster named Sing who
  gets caught between the Axe Gang (the largest
  gang of the time) and old Kung Fu masters (the
  landlord and landlady)
• Sing turns out to be the one and defeats the
  Beast, the number one Kung Fu master

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Overview

• We will look at clips from the movie and analyze
  them in terms of obvious physics mistakes, and
  then we will look at data of actual punches and
  kicks and apply them to what we saw

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Common Problems

• Some common problems to look for are
• Center of mass is ignored
• Spontaneous rotations and forces in mid flight
• Gliding with no vertical velocity
• Ridiculous jumps, hits, and yells

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The Chase
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The Chase

• Human beings cannot run that fast (est. 35 m/s)
  The fastest speed ever recorded of a human being
  running is about 15 m/s
• As Sing turns, there is no banking on the road
  and the friction would not be enough to hold him
  upright
• When the landlady jumps, she starts turning
  spontaneously after she has left the ground, and
  floats at an almost constant vertical velocity
• The landlady sticks to the billboard after the
  initial impact, there she is at rest and there is
  no normal force pushing her to the wall, and
  therefore is virtually no friction

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The Beast v. The Landlord and Landlady
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The Beast v. The Landlord and Landlady

• The beasts face is too flexible and would be
  broken or at least bruised after an impact like
  that
• L and L glide at the Beast
• The Lions Roar would bounce back off walls and
  earth and affect the landlady
• Humans cannot karate chop through iron
• The Lions Roar is a very high pitched sound,
  but it shatters wood, which has a very low
  resonant frequency (about 100hz, the human voice
  can produce at lowest about 500hz)
• The shout shatters wood, glass, and stone in the
  same instant, meaning that the yell has multiple
  frequencies, which is not possible for one wave
• They would all be deaf at the first yell because
  at 85db humans begin to experience ear trauma

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Continued

• When The Beast throws Sings body up, his body
  does not rotate correctly
• If Sing were punched in the head that hard, it
  would be pulverized before it could break the
  ground
• He is then carried off at a ridiculous speed
  (enough to blur the scene behind them)
• Bad guy would not have remained standing after
  his head was severed
• Center of mass for a head is not centered at the
  spinal column, so the head would have spun off
  instead of rotating in circles

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Final Battle
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Final Battle

• Sing jumps and kicks multiple times in the air
  without altering his horizontal or vertical
  velocity
• Peoples mouths cannot bulge that big without
  breaking the skin
• Feet are not that elastic and would have broken
  instead cartoonishly flattening and returning
• The human skull cannot be battered through 10
  thick concrete walls and not be pulverized
• No human or frog can jump that high, the highest
  jump is about 8ft meters by a 7 foot man, even if
  a 5 foot man were to jump 6/5ths his body height,
  he would still only jump 6ft high
• No one can leapfrog with that great a force

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Continued

• The amount of force required to send a person
  that high in the air would kill him
• The amount of force exerted on a person stopping
  from that height would kill him
• When sing ascends, he does so with a constant
  velocity, then starts to decelerate when it looks
  cool
• His hands would not catch fire
• There is simply nothing that would cause the
  Buddhist palm to work, Sing experiences no
  reactionary force when he blows a hole in the
  ground and the building, and there is not even
  energy being lost from anywhere.

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Reality of Punching

• Kung Fu 612lbs.
• Karate 816
• TKD 917
• Boxing 993
• Of these punches, only TKD and Boxing produce
  knockouts, but do not send the receiver flying
  back 10m because of their short impulse and
  because of the bodys limb-based structure

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Reality of Kicking

• Karate 1023lbs.
• Kung Fu 981
• TKD 1572lbs. Or 6992N
• All of these kicks are very powerful but still do
  not have the impulse or momentum to produce
  dramatic effects as seen in the movie. Their
  effects are concentrated and short, only knocking
  the reciever back a few feet at most

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Maph
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(No Transcript)
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Conclusion

• Because of the movies complete ridiculousness and
  flaunting of its physical lawlessness not very
  much of the cool things shown are possible
• Real fighters must train, being the one does
  not automatically give you superior coordination
  and kung fu moves
• P.S. I resent the absence of Bruce Lee from this
  presentation