The initial elastic potential energy stored in the spring is:
Then, the spring is released, all this potential energy is converted into kinetic energy of the eraser:
Then, the force of friction does a work to stop the eraser in this motion, and this work is equal to where F is the magnitude of the friction force and d is the distance covered by the eraser.
For energy conservation, the work done by the friction force must be equal to the initial energy of the eraser, so: and so we find d:
It <span>Ions were once atoms with the same number of electrons and protons. Since they have opposite charges atoms are neutral. When they become ions the lose or gain electrons and become unbalanced. ... These different charges are attracted to each other via electric forces.</span>