Kenimatic Equations for Constant Acceleration 3. Treat horizontal and vertical forces independently

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1 AP Physics Review Forces AP Physics Review D Motion Problem Solving Strategy: 1. Sketch a free body diagram of the problem. Label all forces. Problem Solving Strategy: 1. Sketch the path of the projectile, including initial and final position, velocities, and accelerations. Kenimatic Equations for Constant Acceleration 3. Treat horizontal and vertical forces independently mv Fc = r 3. Treat horizontal and vertical motion independently ~ Clearly label x and x, y and y forces. ~ Sum all forces in the x direction. Same with y. Torque = F is perpendicular ~ Time is the only variable that can be used in both the x and y directions ~ a = 0 in the x direction unless otherwise stated.. Resolve forces at angles into x and y components (unless inclined plane) Combine to get Fc. Resolve the initial velocity into x and y components r is length between rotation and F 4. Balanced Forces means a = 0 and v = constant!!! Incline Plane = Parallel and Perpendicular Components ~ a = g = 9.8 m/s = 10 m/s in the y direction. Pulley / Elevator Problems To find a: FN The overall velocity of the projectile at any point of its motion is the vector sum of its x and y components at that point. =F ma = Fg5 Fg3 ook sb a sign match FBig ic hys θ os P 0 F ll 40 v ma = Fg5 FT In Elevator ma = FT Fg3 ma = FN Fg a sign match direction AP Physics Review Momentum Problem Solving Strategy: Use for Collisions or Explosions 1. Sketch a diagram of the problem. Show before collision and after collision. viy = viy vfy = viy 5 kg =m Friction can be up or down the incline plane opposite motion. θ ma = FT Fg a sign match direction Look at 1 Block gs vx = v cosθ viy = viy On Elevator To find T: 1 3 kg F ll viy = v sinθ gc inθ mg 40 0 vtop = vx vtop = 0 m/s =m F Fg yi = y (height above ground) vi(x & y) = 0 m/s vfy = viy vfx = vx vix = vx On the dished line, Δy = 0 m. Resolve momentum's at angles into x and y components (independent) 3. Momentum in x is conserved. Momentum in y is conserved. Impulse changes momentum Inelastic Collision = Energy Lost 4. Elastic Collisions = Energy Conserved y = 0 so Δy = 0 yi = yi On the ground, Δy = yi p m1v1x = px py px = m1v1 p'x = m1v1 = p1x px m1v'1y m1 m m1v'1x vf = y direction only m1 p'y = 0 = p1y py m1v1y py = 0 m Newton's Laws of Motion: AP Physics Review Energy 1. Law of Inertia = An object at rest stays at rest unless acted upon by an unbalanced force. An object in constant straight line motion stays in that motion unless acted upon by an unbalanced force.. Relates Force, mass and acceleration by the equation: FNet = ma Problem Solving Strategy: Do not use for Collisions or Explosions vi = 0 m/s 1. Sketch a diagram of the problem. 3. Action / Reaction. Every force has an equal and opposite force. v4. Direction does not matter for energy. U can convert directly to K. Types of Forces: Δh3 3. Only time direction matters is when an object has an x velocity. FNet = Sum of all forces = Σ F1 F = ma Fg = mg = Force of Gravity = Weight FT = T = Force Tension in a rope or string FN = Force Normal = Surface Push (Perpendicular) Fs = Spring Force Fc = Centripital Force = Perpendicular to Velocity v3 Δh1 4. Set U and K equation to get the short cut equation. v1 Δh4 = 0 v1 = g Δh1 v = g Δh v3 = g Δh3 Δh = total hi v v4 = g Δh4 = 0 5. W = Change in Energy. So W = U = K AP Physics Review Other Equations in Newtonian Mechanics ignore ( ) sign k = sp constant x = stretch / compress AP Physics Review Thermal Mechanics Thermal Expansion Velocity at the Bottom = g Δh L N0 = Avogadro's Number = 6.0 x 103 particles/mole Rate of Heat Transfer FT at Bottom = Fc = FT Fg Time to Swing across and back. T T = period = time for 1 cycle Time to swing across. N N0 1. The ideal gas law is commonly used. They will give you PV graphs and ask for the temperature. PfVf nrtf = ~ You can use this equation to solve for changes. PiVi nrti ~ If you have number of molecules, use the kb equation. Δh Spring is at equilibrium position. F = 0 N.. G = gravitational constant r = center of mass separation Only use if P is constant Ignore the negative sign Spring is at xmax. U is max. K and v = 0 Temperature comes from the motion of a substances molecules. ~ Motion is K... Kave is directly related to Temp! 3. U is internal energy, found by the KE of all molecules, or N Kave. ~ U = NKave = (3/) N KB T = (3/) n R T ΔU = (3/) nrδt ~ It temperature increases, U increases. Not given but need! 4. Work is always work done "On the gas." Spring is back at x = 0 U=0J n= = Number of Moles molar mass N = Number of Molecules or Atoms ½T Tpendulum depends on length & g Lenght increases, T increases m n= T = π L / g vi = 0 m/s Tspring depends on mass & k K and v = max ~ Contract = W ΔQ = mcδt Specific Heat Expand = W ~ If pressure is not constant, than W = Area under the PV Curve Spring is at xmax. U is max. 5. Q is the transfer of thermal energy, govern by the specific heat eq. K and v = 0 ΔU = Q W Q For stationary fluids. h is depth in the fluid. ~ ρ = density of fluid V = volume of object submerged. 5. Bernoulli's Equation, P ρgy ½ρv is a conservation of energy equation. ~ If fluid has no height, ρgy term = 0 Understand that this does not mean that ΔT = 0 ΔU = 0 W The gas is being compressed, so work is done on the gas. This causes more collisions, increasing molecular motion, increasing temperature, increasing U. ΔU = Q 0 or ΔU = Q 0 = Q W or Q = W The area inside the process A B C A is the net work done. AP Physics Review Magnetism 1. A Charge MOVING PERPENDICULAR through a magnetic field feels a force qvb acting on it. ~ The force felt is perpendicular to both velocty and BField ~ Determined by Right hand Rule (Positive Particles / Current) F = qe 1. Like charges repel, opposites attack. W = qed. Electric Field lines show where () charges will go. ~ Point away from ( ) charges and toward () charges. Only equation where the sign of the charge matters! F ~ E Field inside a conductor is 0 N/C. Must be at surface. 3. Electric Potential = V B Potential (Stored) Energy = U 4. Forces are vectors, so you must think about x and y components. Used for induced voltage and current. 5. Charge, q, is quantized. Comes in clumps of qe = 1.6 x C. Potential Energy Stored in a Capacitor ε = V, so 6. Voltage, V can be shown as ε in a circuit diagram. v BLv = IR 8. The voltage drop over any enclosed loop must be 0Ω. ~ Resistors and Capacitors in parallel have equal ΔV. 9. When hooked up in series, Capacitors have equal charge, q. ~ In series resistors have equal current, I. Combine to get P = IR = V/R BField In (B) In this rule, the vector v is in the direction of your thumb and B in the direction of your fingers. The force FB on a positive charge is in the direction of your palm, as if you are pushing the particle with your hand. (A) In this rule, the fingers point in the direction of v, with B coming out of your palm, so that you can curl your fingers in the direction of B. The direction of v x B, and the force on a positive charge, is the direction in which the thumb points. 7. Positive side of battery is the long plate. Current is always positive! R for a wire is equal to ρ, resistivity of wire, length of wire, and Area Because you start at A and end at A, PV is constant, so temperature returns to initial value. If ΔT = 0, then ΔU = 0. AP Physics Review Electricity or ΔU = W Isothermal Temperature stays constant. This means that there will be no change in internal energy. Any work done on the system is accompanied by a loss of thermal energy and visa versa. Pressure is not constant, so you must find the area under the curve to calculate work. It is expanding so work is done by the gas ( W). The gases internal energy, U, must decrease. or Isovolumetric Volume stays constant. This creates a vertical line on a PV Isovolumetric diagram. Since you cannot take the integral (area under the curve) for a vertical line, W = 0. Negative if the temperature decreases ~ If fluid area is so big v = 0 (Top of water tank), then ½ρv = 0 Could be K = qv ΔU = Q PΔV Adiabatic No heat is exchanged with the surroundings. This means that Q = 0. ~ Volume of displaced fluid = volume of object under water. 4. The Volume Flow Rate, FR = Av, has to be constant for a moving fluid. or Positive if work is done on the system Negative if work is done by the system ΔU Positive if the temperature increases 3. Buoyant Force on an object is equal to the weight of the displaced fluid. ρvg A v is Flow Rate. m3/s Isobaric Pressure stays constant. This creates a horizontal line on a PV diagram. For an isobaric possess, W = PΔV ΔU = Q W W 1. P0 is pressure at the top of the fluid in interest. Usually air pressure 1 x 105. P P0 = ΔP AKA Gauge Pressure Thermal Processes Understanding the Signs Positive if energy is transferredinto the system Negative with energy is removed from the system AP Physics Review Fluid Mechanics A segment of a current carrying wire in a magnetic field B. The magnetic force exerted on each charge making up the current is qv x B and the net force on the segment of length L is IL x B BField Out C1 P also = W/t = E/t C Parallel Connection Equal Voltage Drop over all loops 10. VBat = Req Itot Series Connection Equal Charge or Current VBat Ceq = Qtot Charges move in Circular Motion in a BField. Set FB = FC increase brightness. 11. Light bulb brightness is measured in Power (W). Increase P, A B C Velocity Selector How to get Req. Work your way down, then work back up solving for current (charge for capacitors) and voltage. Second Right Hand Rule for a long Current Carrying Wire C = Charged = Unhooked C = Uncharged = Wire RC Circuits 9 μf 1 V 4Ω 4 μf vi X X X X X X X X X X X X X X Velocity Selectors combine E and B to allow charges with a specific velocity to pass through un deflected. FB = qvb, FE = qv, Set equal and solve for v. qe = qvb so v = E/B Two long parallel current carrying wires can attract or repel each other. Each creates its own BField. Their created BFlield's can interact with the current in the other wire and exert a force on the other wire. 9 μf 5 μf Ω 1 V 4Ω 1 V Ω If the switch is open, everything is uncharged. 4Ω 4 μf 5 μf Ω When the switch first closes, the If the switch is open for a long time, capacitors are still uncharged. With the capacitors are fully charged Q = 0F, V also must be 0, due to (Steady state). The now receive all of C = Q/V. If the voltage over the their possible voltage. Also, since they capacitor is 0, it acts like a wire. are fully charged, no more charge or Third Right Hand Rule for a coil of wire acting like a Bar Magnet Electromagnetic Induction Electromagnetic Induction Pulling a wire through BField Moving a magnet toward a coil of wire will induce a current that create a magnetic field that opposes the incoming / outgoing magnet. creates induced ε (V) and I. current can flow through them and they act as if they are unhooked. 1

2 si so Amplitude Rest Line AP Physics Review Waves & Optics AP Physics Review Atomic and Nuclear Physics n = λ Frequency does λ n not change in n. E = hc λ For a Photon 1. Atomic Mass (energy) and Charge must be conserved.. Look for units and use the correct planks constant h. 3. Forms of atomic radiation (I did not cover...) ~ Alpha (α) Decay = Release P and N. Atomic mass 4. Total Internal Reflection θ Incidence θ Reflection Govern by Snell's Law. Use for DeBrogli Wavelength questions. Can substitute mv ~ Beta (β) Decay = N becomes a P and an e is released. ~ Fisson = split nuecleus (mass/energy and charge conserved). ~ Fusion = fuse nuclei (mass/energy and charge conserved). θ Refraction More Dense to Less Dense ~ Toward the Normal More Dense to Less Dense ~ Away from the Normal K max = qv s Stopping Potential / Voltage E E 1 = ΔE = hf 4. Photon energy related to f. E = hf. ~ High f, low λ, high energy. 5. Electrons absorb (release) energy and jump up (fall down) an energy level with a difference of energy equal to the photon. Eye Eye I O Eye Concave Mirror Converging Devises Convex Lens Principle Axis Vertex Images can be upright or inverted, enlarged or Center of Focal Focal Vertex Focal Curvature Point (f) reduced, real or virtual Point (f) (V) Point (f) Energy of the photon K = hf φ Kinetic Energy of Work Function ejected Electron "Toll" Only works for light at the violent end of the spectrum. Violet light has a higher frequency so it has high energy. They love to ask in terms of wavelength. Cuttoff Frequency s i s o h i h o When When real virtual real virtual upright inverted upright inverted Convex Mirror Diverging Devises Concave Lens Principle Axis Vertex Images will be upright, Focal Center of reduced, and real. Focal Vertex Focal Point (f) Curvature Point (f) (V) Point (f) hf c = φ f converging diverging M upright inverted M > 1 = Enlarged M = 1 = 1 > M > 0 = Reduced Mirror Directions: 1. In parallel, out through/away focus.. In through/toward focus, out parallel 3. In through / toward CofC, back through/ away from CofC Lens Directions: 1. In parallel, out through/away focus.. In through/toward focus, out paralle 3. Straight through the vertex Compton Scattering proves light (massless) has momentum. E = hf = pc. De Broglie took it further, said all matter moves in wave motion govern by λ = h/p = h / (mv) n1 = Ground State n = 1 st Excited State ( nd E Level) n3 = nd Excited State Young's Double Slit Experiment m = m = 1 m = 0 m = 1 m = This can happen with sound as well. Proved light is a wave L >>>>>> d If that distance is nλ, then constructive interference If it's ½nλ, then destructive interference 1 Slit... Then d = slit width not slit separat May 10 7:7 AM May 10 7:7 AM May 10 7:6 AM May 10 6:13 AM

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