Ch4_MarguliesM

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Chapter 4

Lesson 1 a-d (Method 4)
**Method 4: SQ3R** S = Survey (Read the heading of each section and the first sentence of each paragraph. Look at the graphics and pictures to get an idea of what the webpage is about.) Q = Question (Turn the headings into questions to set a purpose for reading, as a prompt for note taking.) R = Read (Read the text to answer your questions and write down the answers in note form.) R = Recite (Cover your answers to the questions and read just the questions, answering them from memory.) R = Review (write a summary of your notes, in paragraph form, or talk it out with your parents (or anyone willing to listen..)

**How can you apply Newton's First Law of motion?** Newton's first law of motion is called the law of inertia. This is an object stays 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. This law can be applied in everyday activities such as driving a car when it stops and starts.

**What is Galileo's concept of inertia?** Moving objects eventually stop because of friction. He said that any difference between initial and final heights was due to the presence of friction. The angle of the planes and the final height of the planes were almost equal. Some objects have more engency to resist change than others because it depends on the mass of the object.

**What is state of motion?** State of motion is defined by its velocity. Inertia is the tendency of an object to resist changes in its velocity and acceleration.

**What is an unbalanced force?** <span style="font-family: 'Comic Sans MS',cursive;">This is when two forces act on an object, one being smaller than the other. When two objects forces are balanced they are said to be at equilibrium. They equal in magnitude and opposite direction.

<span style="color: #ea1f1f; font-family: 'Comic Sans MS',cursive;">Lesson 2 a-d (Method 4)
<span style="font-family: 'Comic Sans MS',cursive;">**What is a force and what is its meaning?** <span style="font-family: 'Comic Sans MS',cursive;">A force is a push or pull on an object and they only exist as a result of an action.

<span style="font-family: 'Comic Sans MS',cursive;">**What are the differences between a contact force and an action at a distance force?** <span style="font-family: 'Comic Sans MS',cursive;">A contact and an action at a distance force are both considered interactions. A contact force is when two objects are physically interacting (examples of forces: Normal, tension, friction, air resistance). Action at a distance forces are not interacting with physical contact, but are able to exert a push pr pull despite their separation (examples of forces: gravitational).

<span style="font-family: 'Comic Sans MS',cursive;">**How do you fully describe a force acting upon an object?** <span style="font-family: 'Comic Sans MS',cursive;">You must describe both magnitude and direction. This is shown through free- body diagrams.

<span style="font-family: 'Comic Sans MS',cursive;">**What are the different types of forces and what does each force mean?** <span style="font-family: 'Comic Sans MS',cursive;">Applied, gravity, Normal, friction, and Tension. An applied force is applied by another object, a gravitational force is when massively large objects attract another object towards itself or the weight of an object. A normal force is the support force exerted upon an object in contact with another object. This keeps a book from going through a table. A friction force is the force exerted by a surface as an object moves across it or makes an effort to move across it. Two types of friction forces are static and sliding. A tension force is the force transmitted through a string, rope, or chain and this is when the force is directed along the length of the wire and pulls equally on the objects on the opposite ends.

<span style="font-family: 'Comic Sans MS',cursive;">**What is the difference between mass and weight?** <span style="font-family: 'Comic Sans MS',cursive;">Weight is the force of gravity acting upon an object and the mass of an object is the amount of matter that is contained by the object. The weight of an object is the force of gravity. The mass of an object does not change, however, the weight will depending where it is in the universe.

<span style="font-family: 'Comic Sans MS',cursive;">**What is the difference between static and sliding friction?** <span style="font-family: 'Comic Sans MS',cursive;">Sliding friction is when an object slides across a surface and static friction is when the surfaces of two objects are at rest relative to one another and a force exists on one of the objects to set it in motion.

<span style="font-family: 'Comic Sans MS',cursive;">**What are free body diagrams used for?** <span style="font-family: 'Comic Sans MS',cursive;">These diagrams are used to show magnitude and direction of all the forces acting upon that given object.

<span style="font-family: 'Comic Sans MS',cursive;">**How do you determine Net Force?** <span style="font-family: 'Comic Sans MS',cursive;">An unbalanced force is sometimes referred to as Net Force, which is the vector sum of all the forces that act upon an object. This takes in the possibilities of some forces going in different directions and they will cancel out.

<span style="color: #ed0c0c; font-family: 'Comic Sans MS',cursive;">Lesson 3 a & b (Method 4)- Newton's Second Law of Motion
<span style="font-family: 'Comic Sans MS',cursive;">**What is Newton's Second Law of motion?** <span style="font-family: 'Comic Sans MS',cursive;">This pertains to the behavior of objects that all existing forces are not balanced. It states that the acceleration of an object is dependent upon two variables, the net force acting upon an object and the mass of the object. For this law, the acceleration depends //directly// upon the net force acting upon the object, and //inversely// upon the mass of the object.

<span style="font-family: 'Comic Sans MS',cursive;">**What is the equation to find the net force?** <span style="font-family: 'Comic Sans MS',cursive;">The net force equals the mass times acceleration. The net force and the acceleration are always in the same direction.

<span style="font-family: 'Comic Sans MS',cursive;">**What is the big misconception?** <span style="font-family: 'Comic Sans MS',cursive;">F=ma. That sustaining motion requires a continued force. A Force is not required to keep an object in motion.

<span style="color: #f41515; font-family: 'Comic Sans MS',cursive;">Lesson 3 c - f (Method 4)
<span style="font-family: 'Comic Sans MS',cursive;">**How do you find acceleration?** <span style="font-family: 'Comic Sans MS',cursive;">To find acceleration you use the equation F=ma. This equation stands for the net force equals mass times acceleration.

<span style="font-family: 'Comic Sans MS',cursive;">**How do you find individual forces?** <span style="font-family: 'Comic Sans MS',cursive;">Again, you use Newton's second law which is F=ma. If you know two of the parts of the equation you can find the third.

<span style="font-family: 'Comic Sans MS',cursive;"> **Why do all objects fall at the same rate of acceleration regardless of their mass?** <span style="font-family: 'Comic Sans MS',cursive;">All objects that are falling under the sole influence of gravity fall at 9.8 m/s. When using F=ma, an object with a smaller mass requires a greater force to move it, and an object with a larger mass requires a smaller force.

<span style="font-family: 'Comic Sans MS',cursive;">**Why do objects that encounter air resistance ultimately reach a terminal velocity?** <span style="font-family: 'Comic Sans MS',cursive;">Air resistance is the result of collisions of an object's leading surface with air molecules. Terminal velocity is the termination of the change in velocity due to balanced forces, or when an object stops acceleration. Air resistance eventually becomes large enough to balance the force of gravity, resulting in terminal velocity.

<span style="font-family: 'Comic Sans MS',cursive;">**Why do more massive objects fall faster than less massive ones when there is air resistance?** <span style="font-family: 'Comic Sans MS',cursive;">More massive objects fall faster because they are acted upon by a larger force of gravity. This is because more massive objects will accelerate to higher velocities before reaching a terminal velocity.

<span style="font-family: 'Comic Sans MS',cursive;">**What are two body problems and how are they solved?** <span style="font-family: 'Comic Sans MS',cursive;">These types of problems are characterized by a set of two unknown quantities. Most likely these unknown variables is the accelerations. These are solved by considering the two objects as one. Then a system analysis is done to determine the acceleration of the system. <span style="font-family: 'Comic Sans MS',cursive;">The other way of solving two body problems is by individual object analysis. This is when either one of the two objects are isolated and are considered seperate. Then a free body diagram is constructed of the individual forces that act on the two objects.