Name: gravitational and elastic energy stored
Uploaded: 2023-09-22T11:49:37.000Z
Duration: 1 min 9 s
Channel: JoVE

La energía potencial es la capacidad de un cuerpo para realizar un trabajo debido a su posición.
El cambio de energía potencial gravitacional es el negativo del trabajo realizado sobre un cuerpo por fuerza, igual y opuesta a su peso, al llevar el cuerpo a una posición específica desde una posición de referencia o dato donde la energía potencial gravitacional se considera cero.
Al levantar un cuerpo, el trabajo realizado por la fuerza gravitacional es negativo, por lo que su energía potencial aumenta. Al mover el cuerpo hacia abajo, se observa lo contrario.
La energía potencial elástica es el negativo del trabajo realizado debido a la fuerza restauradora generada en un cuerpo elástico deformado que intenta restaurar su posición no deformada.
Para un resorte comprimido, el cambio en la energía potencial elástica es positivo, mientras que el trabajo realizado por la fuerza del resorte sobre la masa es negativo. Lo mismo se observa cuando el resorte se estira desde una posición no deformada.
Si tanto la fuerza gravitacional como la elástica actúan sobre un cuerpo, la energía potencial es la suma de ambas energías.

<ol>
	<li>Hibbeler, R.C. (2016). Ingeniería Mecánica: Estática. Decimocuarta edición, Nueva Jersey: Pearson. Págs. 598-599.</li>
	<li>Meriam, J.L., Kraige, L.G. y Bolten, J.N. (2016). Ingeniería Mecánica: Estática y Dinámica. Octava edición, Singapur: John Wiley & Sons. Págs. 411-413.</li>
</ol>

energía potencial

Potential Energy

Una fuerza conservativa, como la fuerza gravitatoria o elástica, confiere al cuerpo la capacidad de realizar trabajo. Esta capacidad, medida como la energía potencial, depende de la ubicación o "posición" del cuerpo en relación con una posición de referencia fija o un datum. La energía potencial gravitatoria se considera cero en el punto de referencia. Supongamos que un cuerpo se encuentra a una distancia vertical por encima de un datum horizontal fijo. En ese caso, el peso del cuerpo tiene energía potencial gravitatoria positiva, ya que tiene la capacidad de realizar trabajo positivo cuando el cuerpo se mueve hacia abajo hacia el datum. Del mismo modo, si el cuerpo se encuentra a una distancia vertical por debajo del datum, la energía potencial gravitatoria es negativa, ya que el peso realiza trabajo negativo cuando el cuerpo se mueve hacia arriba hacia el datum. Si se toma la altura como cero en el datum y se considera la distancia vertical hacia arriba como positiva, entonces a una cierta altura por encima del plano del datum, la energía potencial gravitatoria se expresa como el producto del peso del cuerpo y su altura con respecto al plano del datum. Matemáticamente, esto se expresa de la siguiente manera: <img alt="Equation 1" src="/files/ftp_upload/14358/PT_14358_Equation_1.svg" style="text-align: center; height: 15px;"> Si el cuerpo se encuentra a una distancia por debajo del plano del datum, su energía potencial gravitatoria se vuelve negativa. Hay que señalar que el plano del datum para la energía potencial cero es arbitrario, ya que no afecta el cambio en la energía potencial. El trabajo realizado sobre un cuerpo elástico se almacena en el cuerpo en forma de energía potencial elástica. Esta energía está disponible para realizar trabajo sobre otro cuerpo al aliviar su compresión o extensión. Cuando una fuerza comprime un resorte, causa un desplazamiento x, que es directamente proporcional a la fuerza aplicada. La energía potencial elástica del resorte para una compresión de x es el trabajo total realizado sobre el resorte y se expresa de la siguiente manera: <img alt="Equation 1" src="/files/ftp_upload/14358/PT_14358_Equation_2.svg" style="text-align: center; height: 30px;"> Cuando un resorte se estira, la fuerza actúa en la dirección del desplazamiento, realizando trabajo positivo sobre el resorte y aumentando su energía potencial. Lo mismo se observa cuando un resorte se comprime desde una posición no deformada.

Energía Potencial

Una fuerza conservadora, como una fuerza gravitacional o elástica, le da al cuerpo la capacidad de realizar un trabajo. Esta capacidad, medida como la energía potencial, ...

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gravitational and elastic energy stored

Gravitational and elastic potential energy are forms of stored energy from conservative forces. A conservative force, such as gravity or an elastic force, gives a body the capacity to do work. This capacity is measured as potential energy and depends on the body’s position relative to a fixed reference point, or datum.

For gravitational potential energy, the datum is the level where the energy is taken as zero. If a body is above this reference plane, its weight has positive gravitational potential energy because it can do positive work as the body moves back down to the datum. If the body is below the datum, the gravitational potential energy is negative because the weight does negative work as the body is moved up to the reference level.

If height is measured upward from the datum as positive and zero is set at the reference plane, gravitational potential energy equals the body’s weight multiplied by its height. If the body is below the datum plane, the value becomes negative. The choice of zero potential energy is arbitrary, because only the change in potential energy matters.

Elastic potential energy is stored when work is done on an elastic body, such as a spring. This stored energy can later do work on another body as the spring returns toward its original shape. When a force compresses a spring, it produces a displacement x that is directly proportional to the applied force, and the elastic potential energy is the total work done on the spring.

A stretched spring also gains elastic potential energy because the force acts in the same direction as the displacement and does positive work on the spring. The same increase in potential energy is seen when a spring is compressed from its undeformed position.

Gravitational and Elastic Energy Stored

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Gravitational and elastic potential energy are forms of stored energy from conservative forces. A conservative force, such as gravity or an elastic force, gives a body the capacity to do work. This capacity is measured as potential energy and depends on the body’s position relative to a fixed reference point, or datum. For gravitational potential energy, the datum is the level where the energy is taken as zero. If a body is above this reference plane, its weight has positive gravitational...

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key terms and concepts

Explore how gravity and springs store energy as potential energy, including positive and negative gravitational values and elastic energy in stretched or compressed springs.

Gravitational and Elastic Energy Stored | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

mechanical engineering

Gravitational and Elastic Energy Stored

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