Is it true or false in a rear-end collision if the back of you head encounters a correctly positioned headrest the head's movement is stoped?

False. In a rear-end collision, even with a correctly positioned headrest, the back of your head may not be completely stopped as the body is subjected to sudden acceleration and deceleration forces. While a properly adjusted headrest can help reduce the risk of whiplash and minimize head movement, it may not entirely prevent it. Other factors, such as the severity of the collision and individual biomechanics, also play a significant role.