By doing so, weld current and force is focused into the small area of the projection, and heat is obtained from the resistance to the flow of the welding current. Due to this heat, the projections collapse and the parts are weld together. Another successful welding technique is capacitor discharge stud welding, which uses weld studs or specially formed bolts for welding instead of projections.
Definition of inert. 1  1 : lacking the power to move. 2  2 : very slow to move or act : sluggish. 3  3 : deficient in active properties; especially : lacking a usual or anticipated chemical or biological action.
I think inertia is a powerful idea.The tendency of a body to resist any change in its motion (speed or direction).The other words to resist any change in its acceleration is called its inertia. Mass can be thought of as a measure of a bodyâs inertia.Inertia means reluctance to change. Inertia reduces a rate of change but cannot stop it. The inertia is the Newton's first law.