Elastic Potential Energy

Level : Conceptual Teacher : Kim

The Potential energy stored in a spring (or any similar object) is known as the elastic potential energy. It is stored by the deformation of an elastic material such as the spring in Figure 1. The energy stored in the spring depends on the distance the spring is deformed (stretched or compressed) and the spring constant, which defines the amount of force required to deform a spring by a certain length (the work done on the spring).[3] The ability to get energy out depends on the material's elasticity.

Elastic potential energy(Ue) is given by the equation:

1 2 Ue= kx 2 where k is called the spring constant, and represents the stiffness of the elastic material, x is distance of stretched or compressed spring.

The elastic properties of a spring depend on both shape and the material of the spring. Therefore, the elastic constant is different for every object. Elastic potential energy increases with the constant of the spring and with the distance stretched.

Application A spring is used to store elastic potential energy in many mechanical devices (like the shock absorbers in cars). This energy can be used in many ways since the spring can remain in its compressed or stretched state for extended periods of time without dissipating energy. Spring potential can also be utilized in control systems or mechanical systems to reduce the impact of disturbance, such as in motor vehicles. In vehicles, the shock absorbers are springs that absorb the energy created by hitting bumps in the road, preventing the energy from disrupting the passenger compartment of the vehicle. Another use of spring potential in vehicles is in regenerative braking systems, where the stored energy is used to give the vehicle a small power boost.

Car Shock Absorbers

Shock absorbers are a critical part of a car suspension system. They dampen the extension and compression of the springs, preventing the car from bouncing. Shocks soften the impact of hitting the bumps and holes in the road. When shocks work correctly, the car holds the road better during braking and turning. As shocks wear down, they can contribute to losing control of the car and putting passengers at risk. If the car continues to bounce and sway after hitting a bump in the road, the car should be brought in for service. It is also recommended that shock absorbers be replaced every fifty thousand miles. Having your shocks absorbers inspected at regular intervals and replaced as needed helps to maintain your vehicle’s proper handling characteristics