Density: p m V Average speed: v Average velocity: v x x t Average acceleration: a x d t Instantaneous velocity: v x v x t dx dt Instantaneous acceleration: a x dv x dt 4 equations of motion: x xo v vo a x t x xo vo t 1 2 at 2 Projectile motion: 1 (v v o )t 2 2a( x xo ) v 2 vo 2 v xi vi cos i v yi vi sin i ac Centripetal acceleration: at Tangential acceleration: v2 r dv dt a a r at Total acceleration: Period: T 2r v Radial acceleration: v2 a r a c r Relative velocity: v po v po voo Newton’s Laws 1st Law: -Object at rest will remain at rest -Object in motion remains in motion (law if inertia) 2nd Law: -Acceleration of an object is directly proportional to the net force acting on it and F inversely proportional to its mass a m rd 3 Law: -If two objects interact, the force F12 exerted by object 1 on object 2 is equal in magnitude but opposite in direction to the force F21 exerted by object 2 on object 1 F12 F21 Net Force: F ma Force of static friction: Resistive force Low speed: R bv f s s n Force of kinetic friction: High speed: R cv 2 f k k n Differential form: Terminal speed: Law of gravitation: dv b g vv dt m mg mg vT b c mg (1 e bt / m ) b 2mg DA m1m2 r2 Fg G Coulomb’s law: xf Work: W Fd cos Fx dx Work & KE: KE 1 2 mv 2 W KE f KEi KE KE f k x Wotherforces Instantaneous Power: P Average power: P Conservation of energy: Mechanical energy: where Eint f x x dE dW F v dt dt W t Gravitational potential energy: Electric potential energy: q1q2 r2 Hooke’s law: Fs kx xi Kinetic energy: Fe k e U g mgy G m1m2 r q1q2 r KEi U i KE f U f U e ke Emech KE U General conservation of energy: Elastic potential: Us 1 2 kx 2 KE U Eint cons tan t xf Potential energy from force: U f Fx dx U i xi du Force from potential energy: Fx dx p mv Linear Momentum: ptot cons tan t Net Force: dp F dt Impulse: tf I F dt p tf I F ext dt ptot ti ti Inelastic collision: (KE is not conserved) Perfect Inelastic: (Momentum is conserved & stick together) m1v1i m2 v 2i (m1 m2 )v f Elastic collision: (Momentum & KE conserved) m1v1i m2 v 2i m1v1 f m2 v 2 f 1 1 1 1 2 2 2 2 m1v1i m2 v 2i m1v1 f m2 v 2 f 2 2 2 2 Center of mass: m x m2 x 2 xcm 1 1 m1 m2 i mi ri rcm M CM of extended objects: 1 rcm r dm M drcm 1 vcm dt M Velocity of CM: dri 1 i mi dt M i dv 1 Acceleration of CM: a cm cm dt M i i dvi 1 i mi dt M Rocket Propulsion: m v f vi ve ln i m f Rocket Thrust: Thrust ma m i i Mvcm mi vi pi ptot Momentum of system: Radian: m v s t r Average angular speed: i i dv dM ve dt dt Arc length: m a f i t f ti t s r i Instantaneous angular speed: average angular acceleration: d dt f i t f ti Instantaneous angular acceleration: t d dt Rotational Motion (fixed axis/constant ): 1 2 o t o o o t t 2 2 o 2 o 1 o t 2 Tangential velocity: v ds d r r dt dt Tangential acceleration: at dv d r r dt dt Centripetal acceleration: ac v2 r 2 r Moment of Inertia: 2 I mi ri r 2 dm 2 i KE of rotating rigid body: KE R 1 2 I 2 Moment of inertia for extended continuous object: Torque: I pr 2 dv dL Fr Fr sin r F I dt Power by torque: f f i i W d Id Work done by torque: P d dt 1 2 2 I f i 2 L r p mvr sin I Angular momentum: Ltot cons tan t ds d R R dt dt dv d cm R R dt dt vcm Pure rolling motion: a cm KE of rolling object: KE 1 2 1 2 I Mv cm 2 2 Kepler’s laws of planetary motion: 1st: Each planet in the solar system moves in an elliptical orbit with the Sun at one focus a2 b2 c2 eccentricity : e c a 2nd: The radius vector drawn from the Sun to any planet sweeps out equal areas in equal time intervals 3rd: The square of the orbital period of any planet is proportional to the cube of the semimajor axis of the elliptical orbit. 4 2 3 2 a k s a 3 T GM s 2GM R Speed of light: c f Escape velocity: vesc Rydberg formula: 1 1 RH 2 2 n ni f 1 Frequency of emitted radiation: Total energy of hydrogen atom: E n 2 2 me k e e 2 13.606eV En n2 Radius of Bohr orbits in H: Energy levels of H: Ei E f hf rn kee 2r hc 2 n = 1, 2, 3,… n = 1, 2, 3,… E 1 B o o Frequency of radiation emitted: k e e 2 1 1 f 2a o h n f 2 ni 2 Energies of quantum states for H: kee 2 1 En 2a o n 2 n = 1, 2, 3,… Fs kx Hooke’s Law: xt A cost v max A Simple harmonic motion: a max 2 A Angular frequency: Period: T Frequency: f 2 k 2 2f m T m L 2r 2 k g v 2 1 1 T 2 Physical pendulum: g v L r k m Total energy: E mgd I T 2 I mgd bt Position damped oscillation (small): x Ae 2 m cost Angular frequency damped oscillation (small): Fo A Amplitude damped oscillator: Speed of traveling wave: v T k f 2 o 2 k b m 2m m b m 2 2 1 2 kA 2 k Angular wave number: 2 y A sin kx t Wave function sinusoidal wave: d2y 1 d2y dx 2 v 2 dt 2 Linear wave equation: Velocity of wave (stretched): v Wave power: T where m 1 2 A 2 v 2 Doppler effect: v vo f f v vs Standing wave: y 2 A sin kxcos t Normal modes: n 2L n where n = 1, 2, 3,… fn Frequencies of normal modes: Fundamental frequency: f1 v n n n T v 2L 2L 1 T 2L Natural frequency Air column open on both ends: v 4L Closed on one end: fn n Beat frequency: f b f 2 f1 New frequency (beat): Pressure: P F A Archimedes’s principle: f fn n v 2L where n = 1, 2, 3,… where n = 1, 3, 5,… f1 f 2 2 Pressure with depth: B f gV Mg P Po gh Continuity equation: A1v1 A2 v2 1 1 2 2 Bernoulli’s equation: P1 v1 gy1 P2 v 2 gy 2 2 2 Fe q E k e 2 rˆ Electric field: E Electric field at a point: Fe qo E qo r q E k e 2i rˆi Electric field due to a group of charged particles: i ri Q Q Volume charge density: Surface charge density: V A Q Linear charge density: Electric flux: E E A EA cos Electric flux: E E dA E dA surface q E E dA in o B U U B U A qo E ds Electric flux (closed surfaces): Change in potential energy: A Potential difference between two points: V B U E ds A qo Potential difference between two points in a uniform E field: Electric potential: V V ke q r Electric potential due to continuous charge distribution: Q V A U qo Electric potential due to a point charge: Capacitance: C B V E ds Ed V ke Parallel-plate capacitor: dq r C o A d Q2 1 1 2 QV C V 2c 2 2 2 Q q Q dq Work required to charge a capacitor: W 0 C 2C Q Capacitor with dielectric: C o Co Vo dQ I I nqv d A J nqv d Current: Current density: dt A V R Resistance: I A A Energy stored in a charged capacitor: U Power: IV I 2 R Conservation of charge: V 2 R I1 I 2 I 3 qt C 1 e t I t e RC R q vs. t for a charging capacitor: I vs. t for a charging capacitor: t RC Q 1 e t RC qt Qe RC dq t I t I o e RC I vs. t for a discharging capacitor: dt Magnetic force on moving charged particle: FB qv B t q vs. t for a discharging capacitor: b Magnetic force on a current carrying conductor: FB I B I ds B a Magnetic dipole moment of a current loop: IA Torque on current loop: Biot-Savart law: B N B NIA B Ids rˆ o Ids rˆ dB k m 4 r 2 r2 oI ds rˆ B Total magnetic field at a point due to a current: 4 r 2 I I I Magnetic force between two wires: F1 I 1 o 2 o 1 2 2a 2a II F Force per unit length: 1 o 1 2 2a o I Ampere’s law (steady currents): B ds B ds 2r 2r o I I B o o2 r Ampere’s law (interior to R): 2R NI N B o I o nI Toroid: Solenoid: B o 2r m B dA Magnetic flux: d m dB E ds A dt dt d m d Induced emf through coil: N BA cos dt dt Voltage across a conductor moving through a magnetic field: Faraday’s law: V El Blv Motional emf: d m d dx Bx B Bv dt dt dt I Power delivered by applied force: Fapp v IB v R B v R Magnitude of induced current: R d 1 r dB m E 2r 2r dt 2 dt Tangential electric field: d m dI L dt dt N m Inductance of an N-turn coil: L I Inductance: L dI dt 1 Energy stored in an inductor: U m LI 2 2 Um B2 Magnetic energy density: m A 2 o d E Displacement current: I d o dt Maxwell’s equations: d B Q E ds E d A dt o d E B ds o I o o dt B dA 0 Self induce emf: N Resonance frequency of an LC circuit: Poynting vector: Intensity: fo 1 2 LC 1 EB S EB o o I S av Bv 2 Emax Bmax 2 o Radiation pressure (complete absorption): P I c Polarization by selective absorption: I I o cos 2 i r sin 2 v2 Snell’s law: cons tan t sin 1 v1 SOLvacuun c Index of refraction: n SOLmedium v Reflection of light: n1 sin 1 n2 sin 2 1 n1 2 n2 n o n Snell’s law of refraction: n1 sin 1 n 2 sin 2 Critical angle ( for n1 > n2 ) : Magnification: M sin c n2 n1 Im ageheight Object height h h Mirror equation\thin lens: 1 1 2 1 p q R f Focal length of a mirror: f R 2 Refraction through a single curved surface: n1 n 2 n 2 n1 p q R Flat refractive surface: q n2 p n1 Lens makers’ equation: 1 1 1 n 1 f R1 R2 Path difference: r2 r1 d sin Constructive interference for two slits: d sin bright m m = 0, 1, 2,… Destructive interference for two slits: d sin dark m m = 0, 1, 2,… Phase difference: 2 1 2 min Limiting angle of resolution for a slit: a Limiting angle of resolution for a circular aperture: min 1.22 D Lorentz transformations: x x vt y y z z vx t t 2 c Gamma: v2 1 2 c 1 2 1 1 Time dilation: t t p Length contraction: L Spacetime interval: s v2 c2 Lp 2 ct x 2 2 Doppler effect: Source/observer approaching: f 1 fo 1 Observer/source approaching: f 1 fo 1 Relativistic momentum: Rest energy: Kinetic energy: where p mu E R mc 2 Total energy: E mc 2 K mc 2 mc 2 1mc 2 Energy-momentum relationship: E 2 p 2 c 2 mc 2 Energy-momentum relationship for a photon: : 2 E pc u v ux x u v 1 x2 c v t1 t 0 c xb xa c Lorentz velocity transformation for S´→S: ux dp F dt Force in relativity: Blackbody radiation Stefan-Boltzmann law: Wien’s displacement law: R T 4 mT 2.898 10 3 m k Plank’s radiation law: u 8hc5 hc e kT 1 Photoelectric effect: eVo hf h 1 cos 2 1 Compton effect: mc f E h De Broglie relations: hp 1 xp 2 Heisenberg uncertainty principle: 1 Et 2 2 E Particle in a box: 2mL2 Radioactivity: R Half-life: t1 2 dN N o e t Ro e t dt ln 2 ux v u v 1 x2 c 0.693 Rectangle: A bh Triangle: Circle: A r 2 C 2r Parallelepiped: Cylinder: Cone: V r 2 S 2r 2r 2 A r r 2 bh V 3 Sphere: Cube: A 1 bh 2 V wh 4 V r 3 3 S 4r 2 A 6s 2 V s3