Integrating smart devices and communication technologies with the power grid has exposed cyber-physical system to vulnerabilities, posing significant threats to infrastructure and the economy. Evaluating and strengthening the security of cyber-physical systems is crucial for the advancement of the future electricity grid. Attackers target state estimation (SE) as it plays a significant role in the normal operation of power systems. Hence, any manipulation in measurement sets of state estimation can disrupt the stable operation of the power system. This paper discusses topology attacks, where falsification in the network's structure (adding or removing components) can disrupt functionality on various application related to SE. This research aims to execute a topology attack while bypassing techniques for detecting bad measurements, such as normal residual test. Initially, it implements a topology attack for N-1 contingency using betweenness centrality to identify and prioritize the most critical nodes within the power grid network. Subsequently, manipulation within the SE measurement set reveals critical lines. This paper investigates the impact of Coordinated cyber-physical attacks on power systems adhering to the N-1 security criterion, specifically analyzing their effects on optimal power flow (OPF). This paper confirms the effectiveness of these attacks by conducting thorough simulations across various power system configurations.