Captian america physics

In the recent installments in the captain America movies, we see the captain using his shield to knock out the Nazi's during Wii but how doesn't it kill them. as we have seen in the movies when he throws his shield hard, newton's third law states that the amount of force is equal to the thing it transfers its energy to. so as the captain throws hard, the shield should have enough force to decapitate the enemy. also when Peggy shoots cap's shield, it makes a large vibrating sound. this is because the lognioitutional waves in the combustion form a mechanical wave, which is moving left and right in terms of the wave pattern. thank you for listening in the physics in captain America