What Causes An Ionic Bond To Form Between Sodium & Chlorine ?

A10.0 kg cart and a 15kg cart are locked together with a compressed spring between them. they are then released so that the spring pushes the two carts apart. the 10.0 kg cart is moving at 4.5 m/s afterward. how fast is the 15kg cart moving? 3.0 m/s 2.0 m/s 4.5 m/s 5.0 m/s

This is for my 8th grade science class, i really don’t understand. can someone me? , lol.

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?