Name: free-fall acceleration on earth
Uploaded: 2023-09-22T11:49:39.000Z
Duration: 55 s
Channel: JoVE

Considera una signora che spinge un carrello dei bagagli mentre si muove. La forza esterna esercitata da lei accelera il carrello nella direzione della forza applicata.
Se spinge con una forza maggiore, il carrello si muoverà più velocemente. Per fermare il carrello, deve applicare una forza esterna nella direzione opposta al suo movimento.
Se posiziona più bagagli sul carrello, la stessa forza produce un'accelerazione minore nella direzione della forza esterna netta.
Compilando questi, otteniamo la seconda legge del moto di Newton, che afferma che un oggetto accelera proporzionalmente e nella direzione della forza esterna netta e inversamente alla sua massa.
Oppure, la forza esterna netta che agisce su un oggetto è il prodotto della sua massa e della sua accelerazione. Tutti gli oggetti in accelerazione seguono la seconda legge di Newton.

accelerazione dovuta alla gravità sulla terra

La seconda legge di Newton è strettamente legata alla sua prima legge del movimento. Essa mostra matematicamente la relazione causa-effetto tra la forza e i cambiamenti nel movimento. La seconda legge di Newton è quantitativa ed è ampiamente usata per calcolare cosa succede in situazioni che coinvolgono una forza. Tutte le forze esterne agiscono su un sistema e si sommano insieme per produrre una forza netta Fnet. Una forza esterna netta più ampia produce una maggiore accelerazione. Quest'accelerazione è direttamente proporzionale e avviene nella stessa direzione della forza netta esterna che agisce su un sistema.

Inoltre, è ragionevole pensare che l'accelerazione sia inversamente proporzionale alla massa del sistema. In altre parole, Maggiore è la massa (l'inerzia), minore è l'accelerazione prodotta da una certa forza. Gli esperimenti in merito hanno dimostrato che l'accelerazione è esattamente inversamente proporzionale alla massa, così com'è direttamente proporzionale a una forza esterna netta. Si è scoperto che l'accelerazione di un oggetto dipende solo dalla forza esterna netta e dalla massa dell'oggetto. Combinando le due proporzionalità si ottiene la seconda legge di Newton, la quale afferma: l'accelerazione di un sistema è direttamente proporzionale e nella stessa direzione delle forze esterne nette che agiscono sul sistema, ed è inversamente proporzionale alla sua massa.

La seconda legge descrive come un corpo risponde meccanicamente al suo ambiente. L'influenza dell'ambiente è la forza netta, la risposta del corpo è l'accelerazione e la forza della risposta è inversamente proporzionale alla massa.

Newton ha anche delineato la sua seconda legge in termini di quantità di moto: la velocità istantanea in cui la quantità di moto di un corpo cambia è uguale alla forza netta che agisce sul corpo.

Questo testo è stato tratto e adattato da <a href="https://openstax.org/books/university-physics-volume-1/pages/5-3-newtons-second-law">Openstax, University Physics Volume 1, Section 5.3: Newton's Second Law.</a>

Accelerazione dovuta alla gravità sulla Terra

La seconda legge di Newton è strettamente correlata alla sua prima legge del moto. Fornisce matematicamente la relazione causa-effetto tra forza e cambiamenti ...

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Acceleration due to Gravity on Earth

free-fall acceleration on earth

Free-fall acceleration on Earth describes how fast an object speeds up when gravity is the only force acting on it. Near Earth’s surface, this acceleration is nearly constant for many everyday situations.

Gravity pulls objects toward Earth and gives them downward acceleration. This motion is often written as g, and it helps explain why falling objects gain speed as they move downward.

The value of g is commonly used in physics to predict the motion of objects dropped or released near the ground. It is an important idea for understanding motion on Earth and for solving basic mechanics problems.

Free-Fall Acceleration on Earth

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acceleration due to gravity on earth

Free-fall acceleration on Earth describes how fast an object speeds up when gravity is the only force acting on it. Near Earth’s surface, this acceleration is nearly constant for many everyday situations. Gravity pulls objects toward Earth and gives them downward acceleration. This motion is often written as g, and it helps explain why falling objects gain speed as they move downward. The value of g is commonly used in physics to predict the motion of objects dropped or released near the...

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Learn how free-fall acceleration near Earth works, why gravity makes falling objects speed up, and how g is used in basic physics problems.

Free-Fall Acceleration on Earth | JoVE K12

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Free-Fall Acceleration on Earth

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