Why can’t a bullet proof vest protect you from a knife stab?

Question

I mean, it’s designed to stop a bullet which delivers much more force than a human being can ever produce during stabbing

In: 784

Answer 1

“I mean, it’s designed to stop a bullet which delivers much more force than a human being can ever produce during stabbing.”

Any action causes an equal and opposite reaction. If a person can hold the gun, a person can generate the same force.