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

Considere uma senhora empurrando um carrinho de bagagem enquanto se move. A força externa exercida por ela acelera o carrinho na direção da força aplicada.
Se ela empurrar com uma força maior, o carrinho se moverá mais rápido. Para parar o carrinho, ela precisa aplicar uma força externa na direção oposta ao seu movimento.
Se ela colocar mais bagagem no carrinho, a mesma força produz uma aceleração menor na direção da força externa líquida.
Compilando-os, obtemos a segunda lei do movimento de Newton, que afirma que um objeto acelera proporcionalmente e na direção da força externa líquida e inversamente à sua massa.
Ou, a força externa resultante que atua sobre um objeto é o produto de sua massa e sua aceleração. Todos os objetos em aceleração seguem a segunda lei de Newton.

aceleração devido à gravidade na terra

A segunda lei de Newton está intimamente relacionada com a sua primeira lei do movimento. Matematicamente, ela estabelece a relação de causa e efeito entre a força e as mudanças no movimento. A segunda lei de Newton é quantitativa e amplamente utilizada para calcular o que acontece em situações envolvendo uma força. Todas as forças externas atuando em um sistema se somam para produzir uma força resultante Fr. Uma força resultante externa maior produz uma aceleração maior. Essa aceleração é diretamente proporcional e tem a mesma direção que a força externa resultante atuando sobre um sistema.

Além disso, parece razoável que a aceleração seja inversamente proporcional à massa de um sistema. Em outras palavras, quanto maior a massa (a inércia), menor será a aceleração produzida por uma determinada força. Experimentos demonstraram que a aceleração é exatamente inversamente proporcional à massa, assim como ela é diretamente proporcional à força externa resultante. Descobriu-se que a aceleração de um objeto depende apenas da força externa resultante e da massa do objeto. Combinando as duas proporcionalidades, obtemos a segunda lei de Newton, que afirma: a aceleração de um sistema é diretamente proporcional e tem a mesma direção que a força externa resultante atuando sobre um sistema e é inversamente proporcional à sua massa.

A segunda lei descreve como um corpo responde mecanicamente ao seu ambiente. A influência do ambiente é a força resultante, e a resposta do corpo é sua aceleração, com a intensidade da resposta sendo inversamente proporcional à massa.

Newton também descreveu sua segunda lei em termos de momento linear: a taxa instantânea de variação do momento linear de um corpo é igual à força resultante atuando sobre o corpo.

Este texto foi adaptado de <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>

Aceleração devido à Gravidade na Terra

A segunda lei de Newton está intimamente relacionada à sua primeira lei do movimento. Matematicamente dá a relação de causa e efeito entre força e mudanças ...

Education

JoVE Core

Mechanical Engineering

Engenharia Mecânica

Unit 1

Unidade 1

Physics Basics

Fundamentos da Física

KEY TERMS AND CONCEPTS

TERMOS-CHAVE E CONCEITOS

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

introduction to scalers

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vector or cross product

Cross Product of Two Vectors

The cross product of two vectors gives a new vector that is related to both original vectors. It is also called the vector product. In many physics problems, this operation helps describe quantities that depend on direction as well as size. The result of a cross product has a direction set by the two input vectors. It is not the same as ordinary multiplication. The transcript focuses on the vector or cross product as a core vector operation students use when working with vectors in science.

introduction to vectors

Vectors in Motion and Direction

Vectors describe quantities that have both size and direction. They are used in physics to show how motion, force, and other quantities act in space. A vector can be represented with an arrow. The length of the arrow shows the size, and the arrowhead shows the direction. This makes vectors useful for comparing how one quantity points relative to another. Scalars are different because they have size only and no direction. Understanding the difference between vectors and scalars is an important...

units and standards of measurement

Measurement Units, Standards, and SI Basics

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accuracy and precision

Measurement Errors, Accuracy, and Precision

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rules of significant figures

Counting Significant Figures in Measurements

Significant figures help students record measurements with the correct level of precision. They show which digits in a number are meaningful and which only help place the decimal point. In science class, this idea matters when writing and comparing measured values. The rules for significant figures explain how to count these digits in different numbers. Some digits are always counted, while others depend on where they appear in the number. Learning the rules makes it easier to report answers...

random and systematic errors

Measuring Error in Scientific Data

Random and systematic errors affect scientific measurements. Random errors cause values to spread around the true value. They make repeated measurements less consistent. Systematic errors shift measurements in the same direction each time. Understanding both kinds of error helps students judge data quality. Random error can come from small changes during measurement. Systematic error can come from a biased tool or method. Scientists look for these patterns so they can improve results and...

position and displacement

Tracking Motion with Position and Displacement

Position and displacement are key ideas in straight-line motion. Position tells where an object is located compared with a chosen starting point, called the origin. Displacement describes how far and in what direction the object has moved from its starting position. These ideas help describe motion clearly. Position can change as an object moves. Displacement focuses on the change in position, not just the path taken. That makes it useful for comparing motion in a simple and precise way.

position and displacement vectors

Using Vectors to Describe Motion

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mass and weight

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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...

tension

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gravitational force

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key terms and concepts

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

O JoVE Core Mechanical Engineering oferece vídeos animados concisos e de fácil compreensão que abrangem tópicos-chave como equilíbrio, forças, análise de treliças e mecânica estrutural. Explore suas aplicações no mundo real e observe esses conceitos em ação por meio de experimentos conduzidos por cientistas.

mechanical engineering

Free-Fall Acceleration on Earth

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