シャドーイング練習: How Long Can You Balance a Pencil? - 動画で英語スピーキングを学ぶ
レッスンを作成中...
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Balancing a pencil or any other top -heavy object on its tip is quite a precarious task.
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It's easy to see why top -heavy objects are unstable.
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They just want to fall down.
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Any little nudge will put it off balance, with gravity happy to pull its center of mass even more off balance.
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And the more off balance it is, the more gravity pulls until...
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Physicists call this kind of tipping an inverted pendulum, because it's kind of like an upside -down pendulum.
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And, careful mathematical analysis of inverted pendulums will tell you the obvious.
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They're really unstable.
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In fact, these equations predict that
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if a perfectly balanced pencil with a perfectly sharp tip were
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to get nudged off -balance by just one ten -thousandth the width of an atom, it would take only three seconds to fall over.
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There are indeed acrobats who can balance poles with other acrobats on top, and robots that can balance and catch and throw upright sticks,
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and people who make seemingly impossible artistic rock stacks.
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But in all these cases, keeping the objects balanced either requires an active stabilization effort, or else carefully taking advantage of the fact that the balancing point isn't actually a point.
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So the question is this, can you balance a pencil sharpened to a perfect single atom -wide tip on its tip without active stabilization?
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Well, to start, you'd better get rid of all the air bumping off the sides of the pencil, since the kinetic energy of a typical oxygen molecule is enough to destabilize the pencil.
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Remember, if the pencil gets off -center by even one ten -thousandth the width of an atom, it'll fall down in under three seconds.
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And you'd better cool the pencil and table down as close to absolute zero as you can, since the thermal jiggling of their atoms when they're hotter will similarly jiggle the pencil off -balance.
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But even then, matter at very small scales has a spread -out, wave -like nature, which means you can't have both the pencil perfectly upright and not moving at the same time.
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And while this quantum effect is never a real -life inhibitor of precarious pencil balancing, it means you never even could succeed.
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However, it's still fun to see how long you can keep a pencil balanced on your fingertip.
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The shorter the pencil, the harder it is.
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My best time for a standard 19cm pencil was 1 .3 seconds.
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Think you can beat it?
このレッスンについて
「How Long Can You Balance a Pencil?」を使って、シャドーイングで英語を練習しましょう。
毎日15〜30分の練習で、IELTSスピーキングへの自信と実践的な英会話力が身につきます。
シャドーイングとは？英語上達に効果的な理由
シャドーイング（Shadowing）は、もともとプロの通訳者養成プログラムで開発された言語学習法で、多言語習得者として知られるDr. Alexander Arguelles によって広く普及されました。方法はシンプルですが非常に効果的：ネイティブスピーカーの英語を聞きながら、1〜2秒の遅延で声に出してすぐに繰り返す——まるで「影（shadow）」のように話者を追いかけます。文法ドリルや受動的なリスニングと異なり、シャドーイングは脳と口の筋肉が同時にリアルタイムで英語を処理・再現することを強制します。研究により、発音精度、抑揚、リズム、連音、リスニング力、そして会話の流暢さが大幅に向上することが確認されています。IELTSスピーキング対策や自然な英語コミュニケーションを目指す方に特におすすめです。