Motion and momentum GapFill

Distance is how far an object moves, and does not take into account direction.  DisplacementInertiaMassVelocity is how far away from a starting position an object has travelled, and in which direction; it is a vector. Similarly,  massvelocityinertiadisplacement is the speed of an object, taking into account the direction of travel; this is also a vector.
 AccelerationMassInertiaVelocity 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  remain at the same velocityslow downrotatebe stationary.
Newton's second law can be stated by the equation  force = mass × accelerationforce = mass × acceleration²force = mass ÷ accelerationforce = ½ mass × velocity².
Newton's third law states that when two objects interact,  they eventually come to a stopone exerts a larger force on the otherfriction causes them to heat upthey each exert opposite and equal forces on the other.
 WeightMomentumForceInertia 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  thinking distance ÷ braking distancethinking distance + braking distancebraking distance ÷ thinking 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 conditions, car speed or worn tyresdistractions, alcohol or tirednessroad quality, car size or alcoholtiredness, car weight or weather. Braking distance can be affected by factors such as  the weather, car speed, or quality of brakes and tyresdistractions, car speed or worn tyrestiredness, car weight or weatherdistractions, alcohol, tiredness or car speed.

Momentum is a property of all moving objects, given by the equation momentum =  mass × velocity½ mass × velocity²mass × accelerationmass × acceleration². Momentum is conserved in all interactions.