1. Physics 1 Review
AP Physics 2

2. Defining the important variables
Kinematics is a way of describing the motion of objects without describing the causes. You can describe an object’s motion:
In words Mathematically Pictorially Graphically
No matter HOW we describe the motion, there are several KEY VARIABLES that we use.
Symbol
Variable
Units t
Time s a
Acceleration
m/s2
x or y
Displacement m
Vo or Vi
Initial velocity
m/s
V or Vf
Final velocity
g or ag
Acceleration due to gravity
m/s/s

3. The 3 Kinematic equations
There are 3 major kinematic equations than can be used to describe the motion in DETAIL. All are used when the acceleration is CONSTANT.

4. Common Problems Students Have
I don’t know which equation to choose!!!
Equation
Missing Variable x v t a

5. Graphical Analysis of Motion

6. Position vs. Time Y-intercept signifies the starting point
Slope signifies the velocity (speed and direction)

7. Moving Away
faster
Changing velocity
Constant velocity
slower

8. Moving Toward getting faster Changing velocity Constant velocity
getting slower

9. Velocity vs. Time You cannot point to a position using a v/t graph.
Displacement is the area under the curve
Y- intercept is the starting velocity
Slope… is a change in velocity (acceleration!)

10. Positive Velocity (moving away)
getting faster
Changing velocity
Constant velocity
getting slower

11. Negative Velocity (moving toward)
getting faster
Changing velocity
Constant velocity
getting slower

12. What does this graph tell us?
 This part tells us that it decreased velocity while it was moving away.
 This point tells us that it stopped. (Also, it turned around)
 This part tells us that it increased velocity while it was moving toward.

13. Acceleration vs. Time
Acceleration is the rate at which velocity changes over time.
Negative does not mean getting slower
Positive does not mean getting faster
Average velocity is the area under the curve

14. So how do you know if its getting faster or slower?
Direction (+ or -) of the velocity compared to direction (+ or -) of the acceleration.
Same sign (++ or --): FASTER
Opposite sign (+- or -+): SLOWER
Negative Acceleration does not mean slower!

15. NEWTON’S LAWS OF MOTION

16. A force is defined most simply as any push or pull.
Newton’s Three Laws of Motion
Newton’s Third Law
Newton’s First Law
Newton’s Second Law
Known as the Law of Inertia
Expressed as
F = ma
Known as
Action-Reaction
If an object exerts a force on another object
The 2nd exerts an equal & opposite force on the 1st
More force = more acceleration
More mass = less acceleration
Moving objects keep moving
Objects at rest stay at rest
Unless acted on by an unbalanced force

17. Inertia
Inertia is the tendency to resist a change in the state of motion (its resistance to acceleration).
Mass is the measure of the amount of inertia.
More mass more inertia

18. Mass
Gravitational mass is the mass of an object measured using the effect of a gravitational field on the object.
Static measurement
Inertial mass is the mass of an object measured by its resistance to acceleration.
Dynamic measurement
Galileo’s Principle of Equivalence

19. Newton’s First Law Law of Inertia
“An object at rest tends to stay at rest and an object in motion tends to stay in motion with the same speed and in the same direction unless acted upon by an unbalanced force.”

20. 2nd Law of Motion

22. Newton’s 3rd Law of Motion
For every action, there is an equal and opposite reaction.

23. Work & Energy

24. Transfer of energy
Transferring energy into or out of a system is doing work.
Energy is transferred into or out of a system by three modes.
Heat (Q) is energy transfer due to a difference in temperature
Radiation (R) is energy transfer by photons/EM waves
Work (W) is energy transfer by external forces

25. WORK
In order for work to be done, a force must be applied to an object AND the force must cause a displacement.

26. Work is a vector
If the energy transfer is from the environment to the system:
Work is positive
The energy of the system increases
Velocity or height increases
If the energy transfer is from the system to the environment:
Work is negative
The energy of the system decreases
Velocity or height decreases

27. Work – Energy theorem W = Δ E
The amount of work done is equal to the change in energy storage.
W = Δ E

28. Efficiency

29. Power