Step 1: Recall the formula for heat produced.
Heat produced in a conductor due to current: \(H = I^2 R t\), where \(I\) is current, \(R\) resistance, \(t\) time.
Step 2: Set up ratio.
Let currents be \(I_1\) and \(I_2\), resistances equal \(R\). Given:
\[
\frac{H_1}{H_2} = \frac{I_1^2 R t}{I_2^2 R t} = \frac{I_1^2}{I_2^2} = 9
\]
Step 3: Solve for current ratio.
\[
\frac{I_1}{I_2} = \sqrt{9} = 3
\]
Step 4: Conclusion.
The ratio of currents is \(I_1 : I_2 = 3 : 1\).