Forces and their interactions GapFill

All measurements can be categorised as either  holorsscalarstensorsvectors (which have size but not direction) or  vectorstensorsholorsscalars (which have both size and direction), which include forces.

Distance is how far an object moves, and does not take into account direction.  VelocityAccelerationMomentumDisplacement is how far away from a starting position an object has travelled, and in which direction; it is a vector. Similarly,  momentumvelocityaccelerationdisplacement is the speed of an object, taking into account the direction of travel; this is also a vector.  DisplacementMomentumAccelerationVelocity 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  fall to Earthspeed upbe stationaryremain at the same velocity. Newton's second law can be stated by the equation  force = mass × velocityforce = mass ÷ accelerationforce = mass ÷ velocityforce = mass × acceleration.

Newton's third law states that when two objects interact,  a non-contact force is producedthey exert forces in the same directionthey each exert opposite and equal forces on the otherone exerts a larger force on the other.  VelocityDisplacementInertiaForce is an object's resistance to acceleration.

Gravity is the attraction of objects to each other; it's responsible for a wide variety of effects, from making sure you stay on the ground to controlling the orbits of planets around the Sun.  WeightForceMassKilogram is the name given to the gravitational attraction between an object and a planet (usually Earth), which acts from a point on an object known as its  centre of forcecentre of kilogramcentre of masscentre of weight, and can be measured using a device called   a massmetera kilogrammetera newtonmetera weightmeter.