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Ch 04 HWDue: 11:59pm on Monday, June 11, 2018To understand how points are awarded, read the Grading Policyfor this assignment.Newton's 1st LawLearning Goal:To understand Newton's 1st law.Newton's Principiastates this first law of motion:An object subject to no net force maintains its state of motion, either at rest or at constant speed in a right line.This law may be stated as follows: If the vector sum of all forces acting on an object is zero, then the acceleration of that object is zero.Mathematically this is just a special case of the 2nd law of motion, when , prompting scholars to advance the following reasons (among others)for Newton's spelling it out separately:1. This expression only holds in an inertial coordinate system--one that is not accelerating--and this law really says you have to usethis type of coordinate system (i.e., Newton's laws won't work inside an accelerating rocket ship.)2. This was a direct challenge to the Impetus theory of motion, described as follows:A mover, while moving a body, impresses on it a certain impetus, a certain power capable of moving this body in the direction inwhich the mover set it going, whether upwards, downwards, sideways or in a circle. By the same amount that the mover movesthe same body swiftly, by that amount is the impetus that is impressed on it powerful. It is by this impetus that the stone is movedafter the thrower ceases to move it; but because of the resistance of the air and the gravity of the stone, which inclines it to movein a direction opposite to that towards which the impetus tends to move it, this impetus is continually weakened. Therefore themovement of the stone will become continually slower, and at length, the impetus is so diminished or destroyed that the gravity ofthe stone prevails over it and moves the stone down towards its natural place.A. C. Crombie, Medieval and Early Modern Science</>This theory is sometimes called the Animistic theory of motion since it envisions a "life force" being associated with motion.Newton's 1st law is often very difficult to grasp because it contradicts various common-sense ideas of motion that may have been acquiredfrom experience in everyday life. For example, unaccounted for forces like friction might cause a ball rolling on the playground to eventuallystop, even though no obvious forces seem to be acting.When studying Newtonian mechanics, it is best to remember this as two laws:1. If the netforce (i.e., vector sum of all forces) acting on an object is zero, the object will keep moving with constant velocity (whichmay be zero).2. If an object is moving with constant velocity (not speed), that is, with zero acceleration, then the net force acting on that objectmust be zero.Complete the following sentences to see if you can apply these ideas.