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Chapter 4 Wikispace!!!
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Physics Classroom Lesson 1 Sections A-D Method 4 11/14/11:
- What is Newtons First Law of Motion? - How is Newtons First Law of Motion applied to everyday life?
 * Section A:**

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

An object will continue what ever it is that it is doing unless it is acted upon by an unbalanced force

An example of this in real life would be a person driving a car with cruise control, then the person steps on the brake.

- How are inertia and mass related? - What keeps an object moving? - How is inertia related to mass?
 * Section B:**

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

Mass is a quantity that is solely dependent upon the inertia of an object

A force is not required to keep an object in motion but a force is required to bring an object to rest

More inertia= More mass (the more mass the more it resists change)

- What is important to know about inertia
 * Section C:**

The state of motion of inertia is defined by an objects velocity

Inertia is the tendency of an object to resist change in both velocity and acceleration

- What are some differences between unbalanced and balanced forces?
 * Section D:**

When all forces acting upon and object are balanced it is defined as equilibrium

Objects that are in a state of equilibrium will not accelerate

Unbalanced forces will however accelerate



Always ask yourself: What forces are acting upon the object and in what direction?

If two forces of equal magnitude come together at opposite directions (it is balanced)

A force is only considered unbalanced when there is an individual force that is not being balanced by a force that is of equal magnitude and coming from the other direction

Physics Classroom Lesson 2 Sections A-D Method 4 11/16/11:
What is a force? What are the different kinds of forces?
 * Section A:**

A force is a push or pull upon an object resulting from the object's //interaction// with another object

A Contact force is a force that result when 2 interacting objects are thought to be physically touching each other (Ex:frictional forces, tensional forces, normal forces, air resistance forces, and applied forces)

An Action-at-a-distance force occurs when 2 interacting objects are not in physical contact with each other, but they can still exert a push or pull in spite of physical separation (Ex: gravitational forces, electric forces, magnetic forces)

//**NOTE THAT SOME QUESTIONS AND NOTES FROM SECTION A CAN BE APPLIED TO SECTION B ALSO**//

How are Mass and Weight different? What is sliding friction and what is static friction and how are they different?
 * Section B:**

Mass is the amount of (stuff) matter that an object contains

Weight is a measure of the force that gravity has upon an object

Sliding Friction occurs when an object slides across a surface

Static friction is friction between two solid objects that are not moving relative to each other.

What steps should one take when drawing a Free Body Diagram?
 * Section C:**



__Things to note when doing a FBD:__ Make sure to label carefully Direction= direction of force Magnitude= size of arrow Arrows are usually drawn from center of the system Only show the system when drawing free body diagrams

What specifically is a net force and how can we find it?
 * Section D:**

Net force can be defined as the vector sum of all the force that are acting upon an object

Balanced force- occurs when all of the forces acting upon the system are equal

Unbalanced Force- occurs when the horizontal and vertical forces that act upon a system do not cancel each other out

Physics Classroom Lesson 3 Sections A&B Method 4 11/17/11:
//What is Newtons Second Law of Motion?// //What formulas are commonly associated with Newtons Second law of motion?//
 * Section A:**

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.

Acceleration depends on both the net force acting on object and the mass of the object.

As force increase acceleration also increases

As mass increases acceleration decreases

Net force (E looking thing next to the f)= m (mass) * a (acceleration)

//What is the misconception associated Newtons Second Law of Motion?//
 * Section B:**

An unbalanced net force causes an objects acceleration

Objects that are moving at constant motion do not require any type of force to remain in motion (Dynamic Equilibrium)