The Physics of car collisions • Newton's Laws of motion. See Figure 1 below. Figure 1 (David Darling (no date)) Newton’s First Law of Motion states that ‘An object continues in a state of rest or in a state of motion at a constant speed along a straight line, unless compelled to change that state by a net force.’ My understanding of this is that this means that moving objects will stay moving and still objects will stay still unless you push or pull on them. In the case of a car collision, once the point of impact is reached, your body will want to stay moving at whatever the speed the car was travelling in before the collision, otherwise known as inertia. The velocity and mass of the body determine what the body will instinctively do. In order to stop the body from doing this, a seatbelt should be worn. This provides force to stop the body’s forward motion. …show more content…
If a car collision occurs between two cars and one has a greater mass then the larger of the two will drive the lighter car backwards. The speed of a lighter car can change quicker therefore is more likely to move through the force of the heavier car as this requires more force than the lighter car can provide. Newton’s Third Law of Motion is one that most people would be familiar with, ‘for every action, there is an equal and opposite reaction.’ If a car collided with a wall, although the wall would more than likely absorb most of the force causing a lot of damage to the car and possibly the passenger, during the collision the force of the car against the wall is equal to the force of the wall against the car. •