What is the term used to describe the energy needed to get a reaction started

Which of these describe conduction transfer of heat between two objects that are touching transfer of heat by the actual movement of war matter the process in which energy is imitated by one of the object transmitted through space and absorbed by another a process in which energy is released by the molecules breaking apart

Amagnetic field applies forces on: a)static chargesb)moving chargesc)water flow

Acoil suspended freely, points in some direction when no current is passed through it . can you tell what will happen when a current is passed though it?