Is a car solid structure?

A car is not a perfectly solid structure. While it's designed to be rigid and strong enough to protect its occupants, it's made of many different materials (steel, aluminum, plastic, glass, etc.) joined together. These materials have different strengths and properties, and the connections between them create points of potential flexibility and deformation. In a collision, a car will deform to absorb impact energy, demonstrating it's not a truly solid, unyielding structure.