Answer
$$
K_{f}=1.02 \times 10^{6} \mathrm{J}
$$
Work Step by Step
$\text { Using Eq. } 8-31 \text { (with } W=0)$ we find
$$
K_{f}=K_{i}+U_{i}-U_{f}-\Delta E_{\text {th }}$$
$$=0+\left(1.53 \times 10^{6} \mathrm{J}\right)-0-\left(5.1 \times 10^{6} \mathrm{J}\right)$$
$$=1.02 \times 10^{6} \mathrm{J}
$$
