Looking for devices that convert Elastic energy to Kinetic energy?

Question

I am looking for devices, like springs, bows, that convert the elastic energy to kinetic energy.

I also would like to know how they work, with physical equations.

I want physical equations and explanation please..

Answer 1

In the ideal state (no friction) energy is completely conserved. Most elastic devices can be modeled by a Hooke's Law spring where the Force=k*x, where x is displacement and k is the spring constant. Since Energy is force integrated over a distance, E=1/2*k*x^2 (x squared). This is the total potential energy stored in the spring/elastic device. When a spring with that much energy is completely released, all the potential energy is converted into kinetic energy. The spring acts on a mass, so it uses Newton's law, F=ma. Integrating that over distance gives E=1/2mv^2 (velocity squared). Now you can set them equal and solve for the velocity.

E(spring)=E(kinetic)
1/2kx^2 = 1/2mv^2
v = sqrt(kx^2/m)

Hope this helps!

Answer 2

Hi. Those wind up airplanes. Catapults. A released balloon.

Answer 3

Sling shot.

Answer 4

eissh walaaa, fayaad you're cheating your way through in STEPS? ill tell the board about you...:P