Final answer:
The increase in the length of wire A can be calculated using the formula: ΔL = (F * L) / (A * Y). By setting up an equation using the given ratios, we can solve for the force applied.
Step-by-step explanation:
The increase in the length of wire A can be calculated using the formula:
ΔL = (F * L) / (A * Y)
Where ΔL is the increase in length, F is the force applied, L is the original length of the wire, A is the cross-sectional area of the wire, and Y is the Young's modulus of the material.
In this case, the lengths of wire A and wire B are in the ratio 4:5, and the radii are in the ratio 4:3. Let's assume the original lengths of wire A and wire B are 4x and 5x units, respectively.
Since the increase in the length of wire A is given as 1 mm, we can set up the following equation:
1 mm = (F * 4x) / (A * Y)
From the given ratios, we can substitute the values of the lengths and radii:
1 mm = (F * 4x) / (16 * A * Y)
By solving this equation, we can determine the value of the force applied.