Motion and momentum GapFill

Distance is how far an object moves, and does not take into account direction.  AccelerationMassInertiaVelocityDisplacementMomentum is how far away from a starting position an object has travelled, and in which direction; it is a vector. Similarly,  accelerationmomentummassinertiadisplacementvelocity is the speed of an object, taking into account the direction of travel; this is also a vector.
 InertiaMomentumMassAccelerationVelocityDisplacement is another vector, and describes the rate at which an object speeds up or slows down.

Newton's laws describe how forces affect motion.
Newton's first law states that if an object has no forces acting on it, it will  slow downrotatespeed upfall to Earthbe stationaryremain at the same velocity.
Newton's second law can be stated by the equation  force = mass ÷ accelerationforce = ½ mass × velocity²force = mass × acceleration²force = mass × velocityforce = mass × accelerationforce = mass ÷ velocity.
Newton's third law states that when two objects interact,  a non-contact force is producedthey eventually come to a stopfriction causes them to heat upthey exert forces in the same directionone exerts a larger force on the otherthey each exert opposite and equal forces on the other.
 VelocityDisplacementMomentumInertiaForceWeight is an object's resistance to acceleration.

Forces are very important when discussing vehicle safety. The distance that a vehicle travels before coming to a stop is called its stopping distance, which is equal to  braking distance × thinking distancethinking distance ÷ braking distancebraking distance ÷ thinking distancebraking distance - thinking distancethinking distance - braking distancethinking distance + braking distance. Thinking distance is the distance travelled by a vehicle before the driver reacts to a hazard or other signal. Braking distance is the distance travelled by a vehicle while its brakes are applied, before it comes to a complete stop.
Thinking distance and reaction time can be affected by factors such as  road quality, car size or alcoholtiredness, car weight or weatherdistractions, alcohol or tirednessroad conditions, car speed or worn tyresage, alcohol or road qualityroad or brake quality. Braking distance can be affected by factors such as  distractions, car speed or worn tyresage, alcohol or road qualitydistractions, alcohol, tiredness or car speedtiredness, car weight or weatherthe weather, car speed, or quality of brakes and tyresroad quality, car size or alcohol.