If velocity decreases what happens to acceleration

Velocity is a vector; the word decreasing only applies to its magnitude (not its direction) which is called speed. If speed is increasing and direction is not changing, then acceleration is positive. If speed is constant then acceleration is zero. If speed is decreasing then acceleration is negative.

Explanation:

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .

their crystal patterns have been disrupted by stress