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-M  AP Physics 1 - Final Exam - Fall 2020
Format:  The exam will be a total of 70-75 min in length and will consist of both multiple choice and free response problems. You will need to bring a calculator and writing utensils.  
 
Study Suggestions: Don’t study the what; focus on the how and the why. For example, how does the normal force change when the angle of incline is increased? Why does this happen? Going back through your old homework/quizzes/classwork and not only re-doing the problems, but also asking what concepts are at play, will aid in you preparing for this exam.See “How To Study” on PowerSchool. Come to tutorial if you have any questions.
I will post review resources on Web Assign and PowerSchool.
Google is also a magnificent tool. Don’t hesitate to google things such as “AP Physics 1 work and energy problems” to find an abundance of practice problems with answer keys online!!
 In your groups, fluff out the study guide below. Add content underneath each bullet point that explains that concept.
Content:
¨  Trigonometry + Algebra
Units

Deriving equations

Vectors
Vector v.s. scalar
Vector have both magnitude and direction
Scalar only have magnitude
Symbol for a vector is an arrow
Length of the arrow indicates the magnitude of the vector
Direction the arrow is drawn indicates the direction of the quantity
1D: either go directly right, left, up, or down
Can use “+” or “-” to define their direction
2D: going at an angle
Cannot use “+” or “-”
Requires an angle (#) and a description to define direction
Vector Algebra (finding the resultant of two vectors, or resolving a 2D vector into its components)

¨  Equilibrium
What is equilibrium
All forces acting on the object sum up to zero. The object is moving at a constant velocity and zero acceleration.
Newton’s First Law
States that an object at rest will stay at rest, or an object in motion will stay in motion (in the same direction at constant speed), unless an unbalanced external force acts upon it (Law of Inertia)
An object is at equilibrium when the Fnet acting on the object is 0 N
An object at equilibrium can either be at rest or moving at a constant velocity
Acceleration = 0m/s^2 for an object at equilibrium
Free body diagrams

Force of gravity= go to force (goes down)
Normal force= perpendicular to the surface  Force of friction= draw force opposite of motion
Incline planes: break gravity down into parallel and perpendicular component (mgsintheta and mgcostheta); mgcostheta is always opposite the normal force
Always draw the free body diagram before you start a problem
Inertia
The tendency of an object to resist changes in motion
The amount of inertia possessed by an object is dependent solely upon its mass
More mass = more inertia = more resistance
Mass, Weight, Normal Force, Tension, Friction (static and kinetic)
Mass : amount of material contained in an object
Measured in kilograms (kg)
Weight (W or Fg) : force due to gravity acting on an object
 Measured in Newtons (N)
Calculated as Fg = mg
Normal force (N or FN) : a force of a surface on an object in contact with that surface
Acts perpendicular to a surface, away
A platform scale reads the normal force
At rest = Fnet = 0
Fg = FN
Mg = FN
Tension (T or F) : force transmitted through a string, rope, cable, or wire when it is pulled tight by forces acting from opposite ends
Directed along the length of the wire (for example) and pulls equally on the objects on opposite ends of the wire
Friction (Ff) : force of a surface on an object acting along a surface
Acts in opposite direction of object’s motion
Static - results when surfaces of two objects are at rest relative to one another
Kinetic - results when an object slides across a surface

Coefficient of friction : μ , a unitless quantity that tells how sticky two surfaces are
Larger μ means more friction
MAX FRICTION : Ff = μ x FN
Inclined Planes
Break gravity down into components
Parallel and perpendicular components (mgsintheta and mgcostheta)
When we calculating the horizontal force acting on the object on the Inclined planes we use the equation mg*sin(θ)
When we calculating the vertical force acting on the object on the Inclined planes we use the equation mg*cos(θ)
¨  Kinematics - the study of motion without considering mass or forces applied
Displacement
∆X = Xf - Xi
Direction and magnitude of the straight line between an initial and final position
Path taken DOES NOT matter, only starting point and end point
Measured in meters
Vector quantity
Define by - or +
Define by the angle measurement
Distance
(d) how much ground is covered during its motion
Velocity
Displacement over time (∆X/t)
Vector quality
m/s
Average velocity
Total distance/total time
Doesn't care about change speed throughout route
Pick two points, draw a straight line, and get the slope
instantaneous velocity
speed at one particular instant 
Determine the slope of the tangent line to curve
Acceleration
Acceleration (a): tells how much an object’s velocity changes per second
Vector quantity
Measured in meters per second (m/s)
When an object speed up, acceleration is in the same direction as motion
When an object slows down, acceleration is opposite the direction of motion
An accelerating object can not be at equilibrium
Kinematics Graphs (x vs t, v vs t, a vs t)
Position vs time
Velocity is slope
Straight line- velocity constant
Curved, change in velocity
Velocity vs time
Slope is acceleration
Straight lines
Motion in One Dimension using kinematics equations

Projectile Motion using kinematics equations
Projectile- object which only force acting on it is gravity
Horizontally launched projectiles
Has initial velocity (vx) but not in y direction
Gain a vertical component and horizontal takes the same
Non horizontally launched projectiles (at an angle)
Initial velocity in x and y direction
Forces
Free body diagrams
A diagram that represents one or more objects, along with the forces acting on those objects
Objects are typically drawn as dots, where the dot represents the center of mass of the object
The forces are always shown as arrows starting on the dot and moving away in the direction the force acts
The length of the arrow represents the magnitude of the force
The arrows are always labeled with the type of force it is
Newton’s 2nd Law
The acceleration of an object is directly related to its net force and inversely related to its mass.
Net force
All forces added together
Fnet=ma
Acceleration
As mass decreases0, acceleration increases
Newton’s 3rd law
States that for every action force, there is an equal and opposite reaction force
All interactions involve an action force and a reaction force. Two objects are always involved
Smaller mass goes faster
The size of the forces on the first object equals the size of the force on the second object
The direction of the force on the first object is opposite to the direction of the force on the second object
Forces always come in pairs: equal and opposite action-reaction force pairs
Multiple object systems
Modified Atwood’s machine and Atwood’s machine
¨  Work and Energy
Work
How do you know work is done?
If ME changes OR there’s an unbalanced external force present
Work is NOT done if no change in energy or balanced external force
How do you calculate work?
W = F x D
  Energy

Mechanical energy
The ability to do work; the sum of all kinetic and potential energy in a system
Systems (when can a system have Ug, when can a system have Us)
Includes all things outputting a force, Earth is in system for Ug
 Conservation of energy
Energy can not be created or destroyed.
Power
Define
Rate at which energy is transferred
Units
Hp, Watts (W); J/S; Nm/s
Calculate
P = W/Δt

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