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Elastic Energy

Elastic Potential Energy, Elastic Potential Energy formula, Examples of Elastic Potential Energy, Spring Potential Energy, Hooke’s Law, Gravitational Potential Energy, Gravitational Potential Energy formula, Examples of Gravitational Potential Energy

Introduction

Elastic Energy

Elastic potential energy is the energy that is conserved as a consequence of exerting force to distort an elastic object. The energy is held until the force is withdrawn, at which point the item returns to its previous shape while performing work. The object may be compressed, stretched, or twisted as a result of the distortion. Numerous things are expressly intended to preserve elastic potential energy, such as:

  • A wind-up clock’s coil spring
  • Stretched bow of an archer
  • A twisted diving board appears just before a diver jumps
  • A twisted rubber band propels a toy airplane
  • A ball bouncing against a surface

A device designed to hold elastic potential energy will normally have a high elastic limit, yet all elastic things have a load limit. When an object is deformed far beyond its elastic limit, it will no longer revert to its original structure.

Elastic Potential Energy

Elastic energy is the mechanical potential energy retained in the conformation of a substance or physiological structure as a consequence of force applied to it. Elastic energy is created when things are temporarily crushed, stretched, or otherwise distorted. Elasticity theory is largely concerned with the development of conceptual frameworks for the kinematics of solid bodies and materials. Mechanical equilibrium sites are estimated using the elastic potential energy equation. The energy is potential since it would be converted into another form of energy, such as kinetic and acoustic energy, when the object’s stiffness permits it to do so in its initial configuration.

Elastic Potential Energy Formula

Elastic potential energy may be calculated using the following fundamental formula:

Elastic potential energy = force * displacement.

It is calculated as the effort needed to extend the spring, which is dependent on the spring constant k and the stretched displacement.

Hooke’s law states that the force used to extend the spring is directly equal to the amount of stretch. That is to say, The displacement of the spring is related to the force necessary to stretch it. It is stated as

P.E. = Magnitude of Force * Displacement.

P.E. = (1/2)kx2

Where,

The spring constant is denoted by ‘k’.

The displacement is represented by ‘x’.

Examples of Elastic Potential Energy:

  1. A fluorescent lamps bulb that has been switched off
  2. Before we switch on our car’s headlights
  3. A radio tower is not operational
  4. A switched-off mobile phone
  5. Solar cells at night
  6. A dark light switched-off
  7. Before turning on a television

Spring Potential Energy

When we deform or lengthen a stretched spring, we feel a force equivalent to the force we apply in the reverse trajectory. However, as soon as the force is removed, the spring returns to its original form. This is referred to as spring potential energy. The spring’s elastic potential energy helps in returning to its original form. In general, it adheres to Hooke’s law.

A spring is employed in practically every mechanical part of our everyday lives, from automotive shock stabilizers to a household gasoline lighter. Spring is employed because of its ability to distort and then return to its normal shape. When spring is elongated or contracted, it generates a force in the opposing trajectory of the change. This occurs because when a spring deviates significantly from its normal position, it attempts to return to it. Hooke’s law provides this force, which allows us to assess the energy contained in the spring.

Hooke’s Law:

Hooke’s Law states that the force required to modify the form of a spring is proportionate to its displacement. In this case, displacement refers to how far the spring has been strained or deformed from its initial form.

Hooke’s Law may be quantitatively encapsulated as follows:

F = –k x

Where,

The spring constant is denoted by ‘k.’

The displacement is represented by ‘x.’

The negative sign indicates that the spring force is a restoring force, acting to bring the spring back to its equilibrium position. The expression for spring potential energy is fairly similar, with the same two quantities.

Gravitational Potential Energy

We all know that a big weight lifted above someone’s head indicates a potentially hazardous scenario. Because the weight is firmly secured, it is not always risky. Our fear is that whatever is generating the force to keep the weight in place against gravity may fail. To use proper physics language, we are concerned with the weight’s gravitational potential energy.

When a body of mass (m) is displaced from eternity to a location under the gravitational influence of a source mass (M) without even being accelerated, the measure of work done in distorting it into the source field is preserved as potential energy. This is referred to as gravitational potential energy. It is symbolized by the letter Ug.

The zero in gravitational potential energy is selected freely, which is intriguing. In other words, we have the option of selecting any vertical level as the position where h=0. A convenient zero point for elementary mechanical issues might be the laboratory floor or the surface of a table. In theory, we might select any point of reference, also known as a datum. If the item passes below the zero point, the gravitational potential energy may even be negative. This isn’t an issue; we just need to make sure that the same zero point is utilized proficiently in the computation.

The formula for Gravitational Potential Energy:

Consider the example of an item of mass m being hoisted through a height h against the force of gravity. The object is hoisted vertically by a pulley and cord, thus the force of lifting the box and gravity, F. If g is the gravitational acceleration, we can compute the work done by the force on the weight by multiplying the magnitude of the force by the magnitude of the force of gravity, F, by the vertical distance, h. This is based on the assumption that the gravitational acceleration is constant across the height h.

The gravitational potential energy equation is:

GPE = m.g.h

Where

m denotes mass in kilogram

g denotes the acceleration due to gravity (9.8 m/s2 on Earth)

h denotes the height above the earth in meters

Examples of Gravitational Potential Energy

  1. The water behind a dam with an increased weight
  2. A vehicle stationed at the top of the ridge
  3. A yoyo before it is unleashed
  4. River water cascading from the peak of the cascade
  5. A book on the tabletop before it falls
  6. A youngster standing at the summit of a swing
  7. Ripe fruit before falling

Conclusion

Elastic potential energy is the potential energy held when an elastic material is stretched or compressed by an external force, such as spring stretching. It equals the work done to extend the spring, which is proportional to the spring constant k and the length strained. All sorts of interactions in a system may be labeled with a matching type of potential energy. The total potential energy of the system is the sum of all the potential energies.