Plan for Today (AP Physics 1) Turn in 7.1 Homework Discuss Review Questions on Final Wrap Up Labs

Final Review Information and Review

What to expect Around 15 problems (+/- 2) That means 6 minutes a problem – this is about the same pace as your tests Don’t spend too long on one or two problems – you won’t finish

Chapter 2 – Constant Velocity Problem Constant velocity problem – v = x/t How this might look is a “How long did somebody have to wait” problem Or a highway drive and what mile marker type problem

Chapter 2 – Constant Acceleration Problem (Linear Motion) Something like a brick sliding across the floor You will use one of the four constant acceleration equations Know three things, solve for the forth Be sure to list givens so you don’t flip flop final and initial velocity and keep everything straight

Chapter 2 – Analysis of Motion Using a Graph Slope of x vs t gives you v. Slope of v vs t gives you a Area under a vs t gives you v. Area under v gives you x. Expect to have to calculate and/or sketch this

Chapter 2 – Free fall in one dimension Same as constant acceleration except we know the acceleration automatically (might not be given it) G = 9.8 m/s/s List givens, use one of the four equations of constant acceleration DO NOT switch between those equations and v = x/t

Chapter 3 – Horizontally launched projectile V = Vx Vyi = 0 Make x/y chart Remember, two things on x side to solve, three on y Time is the only thing that crosses over On x side, use v = x/t On y side use equations of constant acceleration

X/Y Charts

Chapter 3 – Projectile Motion X / Y chart You need to break the initial velocity into x and y components using trig (sin, cos) Don’t be tempted to make pretty triangles to show the motion (see next page) Y side = equations of constant acceleration X side = v = x/t (DO NOT USE EQUATIONS OF CONSTANT ACCELERATION) Range equation – or not

Projectile Motion Diagram

Chapter 3 – Vector Graphical and Algebraic Addition Graphically Set a scale Pick a spot around the middle of the paper Draw to scale carefully measuring lines and angles Be sure to measure the right direction (NE vs. EN for ex) Draw the resultant from the start of the 1 st vector to the end of the last Measure its length and angle

Ch 3 – Algebraic Vector Addition Break each vector into x and y components (using sin and cos) When in doubt, sketch it out to determine if you need sin or cos Determine if vectors are + or – N, E = +, S, W = - Add all x components together and all y components together Use Pythagorean theorem to get the resultant vector Use tan (y/x) to get the angle

Chapter 3 – Relative Velocity (River Crossing) Constant velocity in two directions Use v = x/t in both directions NO equations of constant acceleration Draw the situation out Be sure to pay attention to what the question is asking – how far downstream, velocity relative to the shore, etc Remember similar triangles if needed

Relative velocity picture

Chapter 4

Chapter 4 – description of a demo using Newtons laws Given a situation, be able to describe how each of Newton’s laws tie in Newton’s 1 st law – An object at rest stays at rest and an object in motion stays in motion unless an outside force acts on them Newton’s 2 nd law F = ma Newton’s 3 rd law For every action force there is an equal and opposite reaction force

Chapter 4 – Simple Acceleration Problems Fnet = ma Draw a FBD Solve for Fnet (be careful with directions, breaking forces into x y components) Divide by m to get mass

Chapter 4 – Constant velocity and static problems For both (object at rest or moving at a constant speed) A = 0 so Fnet = 0 Using that piece of information, you can solve for unknown forces in x/y direction (or parallel and perpendicular if down a ramp)

Chapter 4 – Net force and accelerated motion down a ramp or force at an angle Remember for ramps Break forces into parallel and perpendicular Add all forces in parallel direction and all forces in perpendicular Fg = mg Fg parallel = mgsin angle (this is a flip) Fg perpendicular = mg cos Careful with FBD to see this Fn = Fg perpendicular (NOT JUST Fg) Acceleration will be parallel to the ramp (Fnet parallel to ramp) Fnet = ma to solve

Chapter 5 – Application of Work Work = F * d * cos theta Think about when to include cos of the angle Possibility: Find Fnet in the same direction as the motion (distance) and then you NEVER have to worry about the angle Be able to find work of various forces acting on an object Be sure to find the component of force along the direction of the motion

Chapter 5 – Work Kinetic Energy Theorem Work = Change in KE In general, Work = Change in Energy If you know some components, you can solve for others F * x = ½ mvf^2 – ½ mvi^2 Be careful with plugging in values to solve

Chapter 5 – Conservation of Mechanical Energy MEi = MEf PEei + PEgi + KEi = PEef + PEgf + KEf Cancel out what you can Solve for unknowns Don’t go “cancelling mass” happy If you have a mass, plug it in, especially if you have a spring Be sure to work and be careful simplifying and solving for your answer

Chapter 5 – Nonconservative Work Wnc = MEf – MEi Figure out what initial mechanical energy you have and what final ME you have DO NOT cancel mass here because Wnc doesn’t have mass in it (probably) Be able to solve for F or d (W = F * d so once you know Wnc... ) If you solve it this way, Wnc will be negative Can also set up Mei = Mef + Wnc – will be positive this way

Chapter 5 - Power P = W/t Power = Change in ME/t Figure out what type of ME is changing for this problem Also P = F * v for constant velocity ONLY Note: if no work is being done, no power

Chapter 6

Chapter 6 – Application of F * t = m * v Plug in to equation and be able to solve for unknowns Remember it’s change in v, so be able to solve for initial or final given the others Also be able to recognize what the problem is asking for (Impulse? Force?) Written response Like the egg falling - be able to explain why a phenomenon occurs and how it relates to impulse

Chapter 6 – Conservation of Momentum in Simple Systems Pi = Pf M1V1i + M2V2i = M1V1f + M2V2f Be careful to include directions if needed Be sure to pay attention to which mass goes with which velocity or if the masses are combined at some point

Chapter 6 – Ballistic Pendulum (and Complex Collisions in General) Stages (most general) Movement before (Conservation of ME) Collision (Conservation of Momentum) Movement after (Conservation of ME)

Ch 6 – Ballistic Pendulum Stages Collision – Conservation of Momentum M1v1i + m2v2i = vf(m1 + m2) Pendulum (and bullet) rise into the air Conservation of energy Mei = Mef Kei = Pegf Masses are the same here ½ m v^2 = mgh

Elastic Collision in One Dimension Momentum is conserved M1v1i + m2v2i = m1v1f + m2v2f Pay attention to directions Kinetic Energy is also conserved Use this equation: V1i – v2i = -(v1f – v2f) to solve

Chapter 7

Chapter 7 – Constant Angular Acceleration Our constant acceleration equations transformed Same idea – ID variables and solve Should be pretty straightforward

Chapter 7 – Simple Circular Motion Problems ID variables and plug in Fairly straightforward

Chapter 7 – Centripetal Motion Straight forward Solving for tangential velocity, centripetal acceleration or force Plug in values