WEBVTT
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Have you ever watched the Thundermans or even maybe ninja
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movies where you see an opponent standing face to face
3
00:00:09.039 --> 00:00:12.599
in a sword fight? You have your opponent swings, you
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00:00:12.640 --> 00:00:15.720
intercept the blade, twist your wrist, and suddenly your adversary
5
00:00:15.740 --> 00:00:19.460
is flying through the air. That's the kind of extraordinary
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00:00:19.500 --> 00:00:22.949
maneuver Max Thunderman performs in the episode Robin Hood, Prince
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of Pheebs. It looks impressive, but could it actually happen? Again,
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I've seen this in a lot of movies. To answer
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00:00:30.059 --> 00:00:33.270
that question, we need to understand some principles of physics. First,
10
00:00:33.289 --> 00:00:36.649
let's examine torque. Torque is that rotational effect of a
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00:00:36.710 --> 00:00:40.630
force when you turn a doorknob, tighten a wrench. The
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00:00:40.689 --> 00:00:43.229
amount of torque depends on the force applied, the distance
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from the axis of rotation, and the angle of application.
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A sword can act as a lever. By applying force
15
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at the right location, a skilled swordsman can redirect an
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00:00:52.479 --> 00:00:56.880
opponent's blade, potentially causing the opponent to lose balance. But
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here's the problem. Redirecting someone's sword is not the same
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thing as lifting their entire body. Imagine Max's opponent weighing
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170 pounds. For Max to send that person six feet
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00:01:09.000 --> 00:01:12.909
vertically into the air, he would need to supply approximately
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00:01:12.909 --> 00:01:17.250
1380 joules of gravitational potential energy. That's before accounting for
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00:01:17.290 --> 00:01:20.629
energy lost through movement, friction, and the opponent's changing body position.
23
00:01:21.469 --> 00:01:25.849
Now consider angular momentum. Angular momentum describes rotational motion. A
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spinning figure skater demonstrates this principle when pulling their arms
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00:01:29.030 --> 00:01:32.390
inward to rotate faster. During a sword fight, twisting an
26
00:01:32.430 --> 00:01:36.950
opponent's weapon can create rotational forces that influence their balance. However,
27
00:01:36.969 --> 00:01:41.349
there's an important distinction. Rotating a sword doesn't automatically rotate
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00:01:41.390 --> 00:01:45.829
the person holding it. The opponent's wrists, elbows, and shoulders
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move independently, absorbing and redirecting much of that force. Next
30
00:01:50.019 --> 00:01:54.079
comes impulse. Impulse describes how a force acting over time
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00:01:54.159 --> 00:01:57.599
changes an object's momentum. To launch a person upward, Max
32
00:01:57.620 --> 00:02:01.340
would need to generate sufficient upward velocity. For a six-foot
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00:02:01.400 --> 00:02:04.969
vertical rise, that velocity would be approximately six meters per second.
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00:02:05.969 --> 00:02:08.710
If the upward movement were delivered in just one-tenth of
35
00:02:08.770 --> 00:02:11.550
a second, the required average upward contact force would be
36
00:02:11.610 --> 00:02:16.629
roughly 5,400 newtons, including the force needed to overcome gravity.
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00:02:17.469 --> 00:02:21.250
That's an incredible amount of force to transmit through a sword. Finally,
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Newton's third law. Every action produces an equal and opposite reaction.
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If Max exerted enough force to launch his opponent, an
40
00:02:27.789 --> 00:02:29.990
equal and opposite force would act back through his weapon
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00:02:30.030 --> 00:02:33.090
and body. He would need exceptional strength and stability to
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00:02:33.129 --> 00:02:36.620
avoid losing his own balance. Of course, Max is the superhero,
43
00:02:36.639 --> 00:02:40.039
so ordinary human limitations don't necessarily apply. And that's what
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00:02:40.080 --> 00:02:44.319
makes this scene so entertaining. Real sword fighters can use leverage, timing,
45
00:02:44.900 --> 00:02:48.000
and body mechanics to unbalance an opponent, but launching someone
46
00:02:48.039 --> 00:02:50.000
several feet into the air through a simple sword flip
47
00:02:50.020 --> 00:02:53.539
would require an incredible amount of energy transfer and force.
48
00:02:54.379 --> 00:02:57.199
The maneuver might violate the limits of human biomechanics, but
49
00:02:57.219 --> 00:03:01.319
it provides a perfect illustration of rotational mechanics. And that's
50
00:03:01.360 --> 00:03:04.639
probably the real scientific lesson here, folks. A sword can
51
00:03:04.680 --> 00:03:08.300
redirect momentum, but it cannot magically create it.
1
00:00:01.669 --> 00:00:04.330
Have you ever watched the Thundermans or even maybe ninja
2
00:00:04.370 --> 00:00:08.359
movies where you see an opponent standing face to face
3
00:00:09.039 --> 00:00:12.599
in a sword fight? You have your opponent swings, you
4
00:00:12.640 --> 00:00:15.720
intercept the blade, twist your wrist, and suddenly your adversary
5
00:00:15.740 --> 00:00:19.460
is flying through the air. That's the kind of extraordinary
6
00:00:19.500 --> 00:00:22.949
maneuver Max Thunderman performs in the episode Robin Hood, Prince
7
00:00:22.989 --> 00:00:27.550
of Pheebs. It looks impressive, but could it actually happen? Again,
8
00:00:27.649 --> 00:00:30.039
I've seen this in a lot of movies. To answer
9
00:00:30.059 --> 00:00:33.270
that question, we need to understand some principles of physics. First,
10
00:00:33.289 --> 00:00:36.649
let's examine torque. Torque is that rotational effect of a
11
00:00:36.710 --> 00:00:40.630
force when you turn a doorknob, tighten a wrench. The
12
00:00:40.689 --> 00:00:43.229
amount of torque depends on the force applied, the distance
13
00:00:43.250 --> 00:00:46.359
from the axis of rotation, and the angle of application.
14
00:00:46.619 --> 00:00:49.259
A sword can act as a lever. By applying force
15
00:00:49.280 --> 00:00:52.439
at the right location, a skilled swordsman can redirect an
16
00:00:52.479 --> 00:00:56.880
opponent's blade, potentially causing the opponent to lose balance. But
17
00:00:56.899 --> 00:01:00.609
here's the problem. Redirecting someone's sword is not the same
18
00:01:00.649 --> 00:01:05.319
thing as lifting their entire body. Imagine Max's opponent weighing
19
00:01:05.319 --> 00:01:08.959
170 pounds. For Max to send that person six feet
20
00:01:09.000 --> 00:01:12.909
vertically into the air, he would need to supply approximately
21
00:01:12.909 --> 00:01:17.250
1380 joules of gravitational potential energy. That's before accounting for
22
00:01:17.290 --> 00:01:20.629
energy lost through movement, friction, and the opponent's changing body position.
23
00:01:21.469 --> 00:01:25.849
Now consider angular momentum. Angular momentum describes rotational motion. A
24
00:01:25.920 --> 00:01:28.969
spinning figure skater demonstrates this principle when pulling their arms
25
00:01:29.030 --> 00:01:32.390
inward to rotate faster. During a sword fight, twisting an
26
00:01:32.430 --> 00:01:36.950
opponent's weapon can create rotational forces that influence their balance. However,
27
00:01:36.969 --> 00:01:41.349
there's an important distinction. Rotating a sword doesn't automatically rotate
28
00:01:41.390 --> 00:01:45.829
the person holding it. The opponent's wrists, elbows, and shoulders
29
00:01:45.890 --> 00:01:49.969
move independently, absorbing and redirecting much of that force. Next
30
00:01:50.019 --> 00:01:54.079
comes impulse. Impulse describes how a force acting over time
31
00:01:54.159 --> 00:01:57.599
changes an object's momentum. To launch a person upward, Max
32
00:01:57.620 --> 00:02:01.340
would need to generate sufficient upward velocity. For a six-foot
33
00:02:01.400 --> 00:02:04.969
vertical rise, that velocity would be approximately six meters per second.
34
00:02:05.969 --> 00:02:08.710
If the upward movement were delivered in just one-tenth of
35
00:02:08.770 --> 00:02:11.550
a second, the required average upward contact force would be
36
00:02:11.610 --> 00:02:16.629
roughly 5,400 newtons, including the force needed to overcome gravity.
37
00:02:17.469 --> 00:02:21.250
That's an incredible amount of force to transmit through a sword. Finally,
38
00:02:21.449 --> 00:02:24.830
Newton's third law. Every action produces an equal and opposite reaction.
39
00:02:24.990 --> 00:02:27.729
If Max exerted enough force to launch his opponent, an
40
00:02:27.789 --> 00:02:29.990
equal and opposite force would act back through his weapon
41
00:02:30.030 --> 00:02:33.090
and body. He would need exceptional strength and stability to
42
00:02:33.129 --> 00:02:36.620
avoid losing his own balance. Of course, Max is the superhero,
43
00:02:36.639 --> 00:02:40.039
so ordinary human limitations don't necessarily apply. And that's what
44
00:02:40.080 --> 00:02:44.319
makes this scene so entertaining. Real sword fighters can use leverage, timing,
45
00:02:44.900 --> 00:02:48.000
and body mechanics to unbalance an opponent, but launching someone
46
00:02:48.039 --> 00:02:50.000
several feet into the air through a simple sword flip
47
00:02:50.020 --> 00:02:53.539
would require an incredible amount of energy transfer and force.
48
00:02:54.379 --> 00:02:57.199
The maneuver might violate the limits of human biomechanics, but
49
00:02:57.219 --> 00:03:01.319
it provides a perfect illustration of rotational mechanics. And that's
50
00:03:01.360 --> 00:03:04.639
probably the real scientific lesson here, folks. A sword can
51
00:03:04.680 --> 00:03:08.300
redirect momentum, but it cannot magically create it.
