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# A load of 20N on a wire of cross-sectional area 8 x 10-7m2, produces an extensio...

### Question

A load of 20N on a wire of cross-sectional area 8 x 10-7m2, produces an extension of 10m2. calculate Young's modulus for the material of the wire if its length is 3m

### Options

A) 7.0 x 1011Nm-2

B) 7.5 x 1011Nm-2

C) 8.5 x 1011Nm-2

D) 9.0 x 1011Nm-2

### Explanation:

Young's modulus = $$\frac{F}{A}$$ $$\div$$ $$\frac{e}{L}$$

= $$\frac{20}{8 \times 10^{-7}}$$ $$\div$$ $$\frac{10^{-4}}{3}$$

= 7.5 x 1011Nm-2

## Dicussion (1)

• Young's modulus = $$\frac{F}{A}$$ $$\div$$ $$\frac{e}{L}$$

= $$\frac{20}{8 \times 10^{-7}}$$ $$\div$$ $$\frac{10^{-4}}{3}$$

= 7.5 x 1011Nm-2