Cars have convex mirrors instead of flat ones because they give a wider field of view. This means there are fewer blind spots, and the driver can see what's behind the car more clearly. However ...

The convex mirror at the corner of that side of the truck shows what is approaching from behind. It effectively offers another 10 feet of visibility, Rabb says. 5. Keep your head on a swivel Graham ...

The shape of the mirror also makes a difference in our perception. In the U.S., passenger-side mirrors are convex (meaning curved slightly outward), whereas driver-side mirrors are flat.