Why does a properly adjusted head restraint prevent head and neck injuries to occupants in rear-end collisions? explain your answer in terms of the law of conservation of momentum.

When a car hits you in a rear end collision, the car initially has a momentum going in one direction. This causes your car to move in the same direction that car was moving even if you were at rest. So, for conservation of momentum, you initially have momentum going in the east direction for example, after the collision, you will have a change in momentum which causes you to have a velocity in the west direction. This is because you are initially at rest and then there is a sudden change in velocity so when you speed up, that momentum causes you to move backwards. If you don't have a properly adjusted neckrest you could may experience whiplash.

A. they hold atoms  together with a molecule.its a force that exist between molecules. hope this .

There is no graph to look at on here, but i shall explain them to you. a line graph is just in its title it’s a graph with a line running through the dots to show an increase or decrease. a bar graph is used to show how much or how little something is so a comparison. a scatter plot is used to graph points to tell the data. and i don’t know what a histogram is.