Ch4_ChiavelliJ

=Chapter 4 Wiki Page =

toc =Lesson 1 (a,b,c,d) = a. What is Newton's 1st Law of Motion? How is his first law applied to everyday life?

**Newton's 1st Law of Motion/Inertia:** an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force

There will be no change in motion, unless an unbalanced force acts on the object.... otherwise move at constant speed in a //straight// line



"Keep on doing what they're doing" mantra unless acted upon by an unbalanced force

All objects resist changes in their motion

Examples: coffee cup rim in car, car braking to a stop, "water around track"

b. How does inertia factor into motion? What keeps an object moving? How does mass relate to inertia?

**Inertia**- the natural tendency of an object to resist change in its state of motion

<span style="font-family: 'Times New Roman',Times,serif;">Galileo breached the concept of friction affecting motion

<span style="font-family: 'Times New Roman',Times,serif; line-height: 0px; overflow: hidden;">

<span style="font-family: 'Times New Roman',Times,serif;">A force is not required to keep an object in motion, but in fact it is a force that brings it to rest

<span style="font-family: 'Times New Roman',Times,serif;">Mass is a quantity that is solely dependent upon the inertia of an object

<span style="font-family: 'Times New Roman',Times,serif;">More inertia= More mass

<span style="font-family: 'Times New Roman',Times,serif;">The more massive the object......the more that the object resists changes in its state of motion

<span style="font-family: 'Times New Roman',Times,serif;">Inertia is a property that measures how difficult it is to change an object's motion..... THIS IS MASS <span style="font-family: 'Times New Roman',Times,serif;">(Kg)

<span style="font-family: 'Times New Roman',Times,serif;">Weight is a force, which is the pull of gravity on a mass (N)

<span style="font-family: 'Times New Roman',Times,serif;">g=9.8*m/s<span style="font-family: 'Times New Roman',Times,serif; vertical-align: super;">2 <span style="font-family: 'Times New Roman',Times,serif; vertical-align: super;">->>>>> <span style="font-family: 'Times New Roman',Times,serif; vertical-align: super;">w=m*g

<span style="font-family: 'Times New Roman',Times,serif;">c. <span style="font-family: 'Times New Roman',Times,serif;">What are the intricacies of inertia?

<span style="font-family: 'Times New Roman',Times,serif;">The "state of motion" of inertia is defined by its velocity

<span style="font-family: 'Times New Roman',Times,serif;">**Inertia**: the tendency of an object to resist changes in its velocity

<span style="font-family: 'Times New Roman',Times,serif;">**Inertia**: the tendency of an object to resist accelerations

<span style="font-family: 'Times New Roman',Times,serif;">d. <span style="font-family: 'Times New Roman',Times,serif;">What is the difference between a balanced and unbalanced force?

<span style="font-family: 'Times New Roman',Times,serif;">When all forces acting upon an object balance each other out, the object is said to be at **equilibirum** (and thus will not accelerate)

<span style="font-family: 'Times New Roman',Times,serif;">Static: at rest, no motion <span style="font-family: 'Times New Roman',Times,serif;">Dynamic: constant speed

<span style="font-family: 'Times New Roman',Times,serif;">When an unbalanced force acts upon an object, it will accelerate in the direction of the unbalanced force

<span style="font-family: 'Times New Roman',Times,serif;">When all forces are balanced, then the acceleration of the object will be 0 m/s/s

<span style="font-family: 'Times New Roman',Times,serif;">Objects at equilibrium will not accelerate

<span style="font-family: 'Times New Roman',Times,serif;">STEPS FOR DETERMINING B/UB FORCES

<span style="font-family: 'Times New Roman',Times,serif;"> 1. What forces are acting upon the object and in what direction? <span style="font-family: 'Times New Roman',Times,serif;">2. If 2 forces are of equal magnitude and opposite direction, then they are balanced <span style="font-family: 'Times New Roman',Times,serif;">3. A force is unbalanced only when there is an individual force that is not being balanced by a force of equal magnitude and opposite direction

<span style="font-family: 'Times New Roman',Times,serif;">

<span style="font-family: 'Times New Roman',Times,serif;">N>W, a^, v^ a^, increase speed up

<span style="font-family: 'Times New Roman',Times,serif;"> =<span style="font-family: 'Times New Roman',Times,serif;">Lesson 2 (a,b,c,d) = <span style="font-family: 'Times New Roman',Times,serif;">a-b. <span style="font-family: 'Times New Roman',Times,serif;">What is a force? <span style="font-family: 'Times New Roman',Times,serif;">What are the different kind of forces? <span style="font-family: 'Times New Roman',Times,serif;">What are the intricacies of a force in more depth? <span style="font-family: 'Times New Roman',Times,serif;">What are the key differences between mass and weight? <span style="font-family: 'Times New Roman',Times,serif;">What is sliding and static friction?


 * <span style="font-family: 'Times New Roman',Times,serif;">Force **<span style="font-family: 'Times New Roman',Times,serif;">: is a push or pull upon an object resulting from the object's "interaction" with another object

<span style="font-family: 'Times New Roman',Times,serif;">If an interaction is present, there is a force upon both objects, if there is not, there is no forces experienced

<span style="font-family: 'Times New Roman',Times,serif;">2 Basic Force Sectors:

<span style="font-family: 'Times New Roman',Times,serif;">**//Contact forces//**: forces that result when 2 interacting objects are "perceived" to be physically contacting each other (Ex: frictional forces, normal forces, tension forces, air resistance, spring forces and applied forces)


 * //<span style="font-family: 'Times New Roman',Times,serif;">Action-at-a-distance //**<span style="font-family: 'Times New Roman',Times,serif;">: forces that result when 2 interacting objects are no in physical contact with each other, BUT can exert a push or pull in spite of physical separation (Ex: gravitational forces, electric forces, magnetic forces)



<span style="font-family: 'Times New Roman',Times,serif;">Force is a vector quantity that has magnitude and direction

<span style="font-family: 'Times New Roman',Times,serif;">Mass is the amount of matter contained by an object, while the weight of an object is the force of gravity acting upon it


 * <span style="font-family: 'Times New Roman',Times,serif;">Sliding Friction: **<span style="font-family: 'Times New Roman',Times,serif;"> when an object slides across a surface (Ex: pushing a box across the floor)


 * <span style="font-family: 'Times New Roman',Times,serif;">Static Friction: **<span style="font-family: 'Times New Roman',Times,serif;">when the surfaces of 2 objects are at rest relative to one another and a force exists on one of the objects to set it into motion relative to the other object (Ex: you exert 5N of force on a box on the floor, but it remains in place, therefore static friction was present between floor and box keeping it in place)

<span style="font-family: 'Times New Roman',Times,serif;">Key Formulas <span style="font-family: 'Times New Roman',Times,serif;"> <span style="font-family: 'Times New Roman',Times,serif;"> <span style="font-family: 'Times New Roman',Times,serif;">c. <span style="font-family: 'Times New Roman',Times,serif;">What are the key steps in drawing free-body diagrams?

<span style="font-family: 'Times New Roman',Times,serif;">Magnitude= size of arrow <span style="font-family: 'Times New Roman',Times,serif;">Direction= direction of force <span style="font-family: 'Times New Roman',Times,serif;">Labeled with distinction <span style="font-family: 'Times New Roman',Times,serif;">Arrow usually drawn from center <span style="font-family: 'Times New Roman',Times,serif;">Only show system*


 * <span style="font-family: 'Times New Roman',Times,serif;">d. **
 * <span style="font-family: 'Times New Roman',Times,serif;">What is net force, and how is it determined? **


 * <span style="font-family: 'Times New Roman',Times,serif;">If horizontal/vertical forces do not cancel each other out, an unbalanced force is present **

Net Force**: is the vector sum of all the forces that act upon an object

<span style="font-family: 'Times New Roman',Times,serif;">

=<span style="font-family: 'Times New Roman',Times,serif; font-size: 110%;">Lesson 3 (a,b) = <span style="font-family: 'Times New Roman',Times,serif;">a. <span style="font-family: 'Times New Roman',Times,serif;">What is Newton's Second Law of motion? <span style="font-family: 'Times New Roman',Times,serif;">What are the associated formulas?

<span style="font-family: 'Times New Roman',Times,serif;">**Newton's Second Law of Motion**: the acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object

<span style="font-family: 'Times New Roman',Times,serif;">Acceleration is dependent on 2 variables <span style="font-family: 'Times New Roman',Times,serif;">- net force acting on object <span style="font-family: 'Times New Roman',Times,serif;">- mass of object

<span style="font-family: 'Times New Roman',Times,serif;">Depends directly on net force acting upon, and inversely upon the mass of the object

<span style="font-family: 'Times New Roman',Times,serif;">As force increase, acceleration does as well <span style="font-family: 'Times New Roman',Times,serif;">As mass increases, acceleration decreases

<span style="font-family: 'Times New Roman',Times,serif;">a= NET FORCE/m OR NET FORCE= m*a

<span style="font-family: 'Times New Roman',Times,serif;">b. <span style="font-family: 'Times New Roman',Times,serif;">What is the confusion surrounding Newton's Second Law of Motion?

<span style="font-family: 'Times New Roman',Times,serif;">A NET (UNBALANCED) FORCE CAUSES AN ACCELERATION*

<span style="font-family: 'Times New Roman',Times,serif;">A FORCE IS NOT REQUIRED TO KEEP AN OBJECT IN MOTION*