A mass of 2kg is suspended from a fixed point by a wire of length 3m and diameter 0.5 mm. Initially the wire is just unstretched, the mass resting on a fixed support. By how much must the temperature fall if the mass is to be entirely supported by the wire? Given that Y of the wire = 206 G Pa, `alpha=11xx10^(-6)//""^(@)C`.

Explanation

To solve the problem step by step, we will use the concepts of Young's modulus, strain, and thermal contraction.

### Step 1: Understand the problem
We have a mass of 2 kg suspended by a wire of length 3 m and diameter 0.5 mm. The wire is initially unstressed, and we want to find out how much the temperature must fall for the wire to support the entire weight of the mass.

### Step 2: Calculate the force due to the mass
The force exerted by the mass (weight) can be calculated using the formula:
\[ F = mg \]
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