Question

A current of 1.0 A from a 1.0 mm diameter wire enters a sphere which is 1.0 m in radius and exits through a 1.0 mm diameter wire on the opposite side of the sphere. What is the smallest value of current density in the sphere?

Answer 1

The current density in the sphere is 0.32 A/m²

Step-by-step explanation:

Given that,

Current = 1.0 A

Diameter = 1.0 mm

Radius of sphere = 1.0 m

We need to calculate the current density in the sphere

Using formula of current density

`J=(I)/(A)`

Where, I = total current

A = area of sphere

Put the value into the formula

`J=(1.0)/(\pi*(1.0)^2)`

`J=0.32\ A/m^2`

Hence, The current density in the sphere is 0.32 A/m²