A wire of diameter `0.04 cm` and made of steel of density `8000 kg//m^(3)` is under a tension of `80 N`. A fixed length of `50 cm` is set into transverse vibrations . How would you cause vibrations of frequency `840 Hz` to predominate in intensity ?

Explanation

To solve the problem, we need to determine how to achieve a frequency of 840 Hz in a steel wire under tension. Here’s a step-by-step breakdown of the solution:

### Step 1: Calculate the Cross-Sectional Area of the Wire
Given the diameter of the wire is \(0.04 \, \text{cm}\), we first convert this to meters:
\[ \text{Diameter} = 0.04 \, \text{cm} = 0.0004 \, \text{m} \]
The radius \(r\) is half of the diameter:
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