- 21

- 0

**1. Homework Statement**

Consider a platinum wire (σ = 1.0e+7) with a cross-sectional area of 1 mm^2 (similar to your connecting wires) and carrying 0.3 amperes of current, which is about what you get in a circuit with a round bulb and two batteries in series. Calculate the strength of the very small electric field required to drive this current through the wire.

**2. Homework Equations**

σ=qnu

I=qnAuE

Therefore I=σAE

where phi is the conductivity A the cross sectional area and E the electric field

**3. The Attempt at a Solution**

This seemed easy but i got an answer of 3e-5 and that is incorrect?