Given that o.2i+bj+o.4k is a unit vector, what is the value of b?

b = 0.89

Explanation:

The given vector is,

A is a unit vector

We need to find the value of b.

For a unit vector, |A| = 1

So,

So, th value of b is 0.89.

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 .