Two carts connected by a 0.05 m spring hit a wall, compressing the spring 0.02 m. The spring constant k is 100 n/m. What is the elastic potential energy stored from the spring's compression?

I'm not sure what your asking buddy.. but i know that you can weld two peices of steel by pure force and pressure.

In atoms, the electron carries a negative elementary or unit charge; the proton carries a positive charge. the two types of charge are equal and opposite. in an atom of matter, an electrical charge occurs whenever the number of protons in the nucleus differs from the number of electrons surrounding that nucleus.

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