Calculate the initial resistance of the wire. length of wire = 1.0 m, cross sectional area of wire = 2.9 × 10⁻⁸ m2, resistivity of wire = 4.9 × 10⁻⁷ Ω m

The resistance $R$ of a wire is given by the formula:

$$R = \frac{\rho L}{A}$$

where $\rho$ is the resistivity, $L$ is the length, and $A$ is the cross-sectional area.

Given:
$L = 1.0 \text{ m}$
$A = 2.9 \times 10^{-8} \text{ m}^2$
$\rho = 4.9 \times 10^{-7} \Omega \text{ m}$

$$R = \frac{(4.9 \times 10^{-7} \Omega \text{ m})(1.0 \text{ m})}{2.9 \times 10^{-8} \text{ m}^2}$$

$$R = \frac{4.9 \times 10^{-7}}{2.9 \times 10^{-8}} \Omega$$ $$R = 16.89655... \Omega$$

Rounding to three significant figures:

$$R = 16.9 \Omega$$

The initial resistance of the wire is $\text{16.9 } \Omega$.