When the wings of an airplane come to a point at the nose like an arrowhead the shape is called

The arrowhead design of the wing of the airplane is referred to as the Delta wing.

Explanation:

The delta wing is a design of the wing of the airplane when it comes to the nose point of the airplane. This shape is called as the delta wing because it resembles the Greek symbol of delta.

The delta can be seen as the isosceles triangle which represent each side to be equal in proportion, and so does the delta winged air craft or air planes.

conservation of mass

mass before something happens = mass afterwards