-16 Technology gives rise to new physics; similarly physics gives rise to new technologies. • Very short range (10 m ) weak force • Not weak as gravitational force but much weaker than the strong nuclear force and electromagnetic forces. Chapter - 1 Principal Thrust To derive the properties of bigger and more complex system from the properties of its constituent into simpler parts. Scop Classical Physics deals with macroscopic Study of the basic laws of nature Excitemeeand nt of phenomenon and includes subject like Physics and manifestation in different Mechanics, Electrodynamics, Optics and natural phenomenon Thermodynamics. Quantum Physics deals with microscopic phenomena at the minute scales of atoms, molecules and nucleus. Physical World Fundamental Forces of Nature • Very short range, strongest force • Attractive in nature • Range – 10-15 m • Strongest among all fundamental forces. To explain diverse physical phenomena in terms of concepts and laws. Systematic observations, controlled experiments, qualitative and quantitative reasoning, mathematical modelling, prediction and verification or falsification of theories. • Any subject is said to be science when it is studied in sequence pattern. The experimenting, exploring and predicting from what we see around us. • Force of mutual attraction between any two objects by virtue of their masses • Plays a key role in large scale. • The phenomena of the universe, such as formation of and evolution of stars, galaxies and galactic clusters are by gravitational force governed. • Force between the charged particles • Both attractive and repulsive • It is 1036 times stronger than gravitational force between two protons, for any fixed distance. Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 1 mean = 1 ( ∆a δa = ∆a mean × 100 amean n + ∆ a2 + ...+ ∆ an Percentage Errror ∆amean = ∆a = mean amean n a1 + a2 + ...... + an Relative Errror a ∆an = an – amean Absolute Errror ) Types ±∆ Z= ± ∆ A ± ∆ B All non-zero digits All zero between two non-zero digits If the number is less than 1, the zero(s) on the right of decimal point but to the left of the non-digit zero are not significant. Terminal or trailing zero (s) in a number without a decimal point are not significant e.g In 020342.010 Here 20342.01 are significant Comparison with a certain internationally accepted reference standard is called unit Reference standard use to measure physical quantities. Measurement Units and Measurements ∆Z ∆ A ∆B = + Z A B ived Z = A ×B / C q r ∆Z ∆A ∆B ∆C = p + q + r Z A B C If p Universal acceptance Non-perishable Well defined Does not change with time Quantities plane angle and solid angle have radian and steradian as units (Internationally accepted) S.I - System International MKS– Metre, Kilogram, Second FPS – Foot, Pound, Second CGS – Centimeter, Gram, Second Set of fundamental and derived units The units which are derived from fundamental units are called ts derived units. Physical quantities like speed acceleration have derived units like m/s, m/s2 uni Mass, length, time, temperature, electric current, luminous intensity and amount of substance have fundamental units. Kilogram, metre, second, Kelvin, ampere, candela and mol respectively. Closeness of the measured value to the true value ity nt a u er w po If Z=A/B Der ts ni Chapter - 2 Pr op er tie s Limit of resolution of quantity measured. Types Me a rai sed sure d to q th e Combination of Errors in Error = True Value – Measured Value Expression which shows how and which of the base quantities represent the dimensions of a physical quantity is called dimension formula. e.g:- Force = MLT –2 Mind map : learning made simple Unit Fund am e nta lU m ste Sy its un f o Multiplication or Division 2 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI x = v0t + at (ii) In opposite direction, it will be Difference In same direction, it will be Sum vavg Rate of change of position of an object w.r.t time in given direction .Vector Quantity Av er ag e = ∆x ∆t Total displacement = Total time taken ity oc l Ve (ii) vAB = vAn − vB vBnA = vBB − vA a ( 2n-1) 2 Types Motion in a Straight Line t Rate of change of velocity, a = v Chapter - 3 orm ∆x vinst = lim ∆t → 0 ∆t = dx dt Av e The shotest distance traversed by any object in called displacement It in a vector quantity. Total length of the path traversed by any object is called its distance It is scalar quantity. When the magnitude or the direction of velocity changes w.r.t. time. Equal distances are traversed in equal amount of time. v 1t 1 + v2 t2 + ..... + vn tn t 1 + t 2 + ..... + t n When object traversed different speeds in different time of intervals. s1 s2 s3 s + + + ...... n v1 v2 v3 vn When object traversed different distances with different speeds. Distance traversed/time taken . Scalar quantity ment Displace e tanc Dis n o ti o n ti o Mo Non - uni form m if Un ed pe eS g ra (i) (iv) xnth = v0+ 2 2 (iii) v = v0 + 2ax v = v+ at 0 (i) Free Fall ns of quatio tic e a n motion nem cceleratio Ki a y l rm i fo un Earth’s gravity (g= 9.8m/s2). On neglecting air resistance, it is a case of motion with uniform acceleration. e.g Apple falling from a tree. An object falling because of Total time interval ∆v = ∆t Total change in velocity Accel eration aavg = Ve locity ∆v dv a inst = lim = ∆t → 0 ∆t dt Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 3 2 Horizontal range,R = u sin2θ g Total time of flight,Tf = 2u sinθ g Maximum height,Hmax = u2sin2θ 2g Vectors having common starting point. If, A = – B Vectors having same magnitude but opposite direction eg. A is a negative of B Vectors having same direction and magnitude gnitu It has magnitude as one or unity A ^ A = A y=x tanθ– Equ Pla ne tile jec n o tio Pr mo Mo tio ni na Motion in a Plane x=(ucosθ)t; y=(u sinθ) t - 1 gt2 2 Motion of an object that is in flight after being thrown or projected. r Vec to → P tile ation of path of projec g x2 2u2cos2 → P Law of Parallelogram Law of Triangle → → → R=P+Q → → → → R R Q Q Addition of Vectors at any instant po ax = 0,ay = g C o m → → |V & AB|=| VBA| → → VAB = –VBA →→ → → V BA = VB –VA → → → V AB =VA –VB ac=v2/r = rw2 = 4π2 rv2 A body in a circular motion acted upon by an acceleration directed towards centre of the circular motion. Angular velocity ,ω= θ/t Angular acceleration,d=∆ω/∆t eg- merry go around. When an object follows a circular path at a constant speed , the motion of the object is called uniform circular motion. → a = axi + ayj; ax=dvx/dt & ay= dvy/dt → |a|=√ax2+ay2 → v =vx i + vy j , → magnitude|v | = √vx2+vy2 → i + y^ j Position vector , r = x^ → Displacement vector , ∆ r = ∆ x^ j i +∆y^ → → λ × A=λA u= ucosθ,u= u sinθ x y Motion of Body under 2 dimensional frame. →→ → → A–B=A+(–B) Chapter - 4 ne It has zero magnitude and orbitary direction Mind map : learning made simple ele r a ti o n f acc Centripeta l n ts o 4 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI Acce lera tio n n io ct mv R Opposes impending relative motion FS = µsR Ce ntr n ctio Fri ip e t a l f o r c e Force which opposes the relative motion of a body Centrifugal force is equal and opposite to centripetal force. F= 2 on est Kinetic Fric tion , e g car A push or pull which changes or tends to change state of rest or of uniform motion of a body. Oppose actual rolling motion µ R < µk < µs tion fric g llin Ro Oppose actual relative motion Fk = µkR e Laws of Motion Types In rt ia of m w o tion h c o e n m o ving me s i n r e st A particle is said to be in equilibrium when net external force on the particle is zero. F1 + F2 + ..... + Fn = 0 M om en t ton’s law of New tion of mo Resistance to change its state of rest or motion. Ne Product of mass and velocity of the body p = mv II l a w mAuB + mBuB = mAvA + mBvB The total momentum of an isolated system of interacting particles is conserved dt Impulse = force × time I = change in momentum I = mv − mu I = m ∆v Total change in momentum To every action there is always an equal & opposite reaction. FAB = FBA Action & reaction act on two different bodies where ‘a’ = acceleration The rate of change of momentum of a body is directly proportional to the applied force and takes place in the direction in which the force dp acts. ∝ F ⇒ F = ma oti o n o n’s of m wt law ’s on rtia Ine Every body continues to be in its state of rest or uniform motion unless acted upon by a non-zero n external force. o i t Mo Also called law of Inertia. of Chapter - 5 lse pu Im Maximum value of static friction n ca ro n Force which makes a body move along a circular path with a uniform speed. a car on bank ed r oad Moti on of a When friction force is taken into consideration ½ µ + tan θ v max = Rg s 1 − µ s tan θ When no friction force is considered v max = Rg tan θ of on oti M Vmax = µS Rg a d roa el v le ) (P Limitin g fri cti o st Fo r c e n io ot m of St a t ic fri re um of conservation Law of momentum r r in i eg, when a c a m ot co m e s i n of In e rti a aw II l ’s I n o t New article of a p ium ibr uil Eq Ne w t Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 5 When force and displacement are perpendicular to each other. W = zero when θ = π 2 When force (F) and displacement (S) are in opposite direction. W will be (-ve) when π <0<π 2 When force (F) and displacement (S) are in same direction. π W will be+ve when 0<θ< 2 An instance of one moving body striking against another Types Z o er rk wo s Type • Total energy and linear momentum conserved. • Kinetic energy not conserved. ( ) Time ( t ) Work w Power ( P) Work, Energy and Power 1hp=746watt 1kWH=3.6 × 106J ds Pinst . = F ⋅ = F ⋅ v dt P = s2 1 1 W = ∫s Fdscosθ = ∫s F ⋅ ds s2 Work done by a variable force W = Fscos θ = F⋅ s Work is said to be done when force produces displacement. Work done by constant force y rg Types of mechanical energy Capacity of doing work Various forms 1 1 mv 2 – mu2 = W 2 2 Change in Kinetic Energy = Work done by net force on the body i.e; By virtue of position Ep = mgh k= spring constant P ote n 1 U = kx 2 2 1 p2 E K = mv 2 = 2 2m By virtue of velocity Nuclear Energy Electrical Energy Chemical Energy Heat Energy Energy can neither be created nor destroyed; it can only be transformed from one form to another. Equivalence of mass and Energy E=∆mc2 Formula Rate of doing work Kine tic E n erg y • Total mechanical/kinetic energy is conserved. • Momentum is conserved. En e Chapter - 6 ti a lE ne r Mind map : learning made simple ri n g f Sp (W) Work gy o 6 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI mo me nt of fo rc e Vcm = n i i i=1 mi n i =1 I = ∑mi ri 2 Inertia of rotational motion, M.I., Systems of Particles and Rotational Motion Vcm = n i=1 i ∑m i =1 n ∑m v i i The point where the whole mass of the system is supposed to be concentrated e ody Rigid b tion us of gyra Radi ax i =1 n acm = ∑ Acc ele rat ion mas so f th of c e es ys te i mi ai ∑m ass for rigid bodie s tre of m Cen el body ped a h rs ula of p reg Theorem e som of a i t ter f in o t en om M ll ara I = I cm + mr 2 Icm = M.I.about the parallel axis through the centre of mass is independent of the state i.e., rest or motion of the body. A body with perfectly definite and unchanging shape. n r12 + r2 2 + ........ + rn 2 I K= m K= mI 2 12 2 I one edge = mI 3 (2) Ring I cm = mR2 2 Idiameter = mR 2 2 (3) Disc I cm = mR 2 2 Idiameter = mR 4 (4) Solid sphere Idiameter = 2 mR2 5 (1) Rod I cm = Chapter - 7 of re t n m ∑ i =1 n ∑m r mass e of r t cen tem of n sys o e i it th of Angular m omen tum Torque or c oup le o r Position of centre of mass of an object changes in translatory motion but remains unchanged in rotatory motion. Position of centre of mass depends upon shape, size, distribution of mass of the body. L= Ιω = mvr = r × mv L= r × p = rpsinθ → → → ^ τ = r × F = r Fsinθ n^ τrotational = Ια perpendicular axes x, y and z respectively Th eo Equ rem atio of p ns of erpe ax ndicular ro es Theorems of moment tat io of Inertia na Po s Moment Inertia e of Centr mass ion ot lm Velocity of Center mass of the system s Iz = Ix + I y I x , I y & I z moments of inertia about Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 7 2m L 2 3 = Constant Gm r2 −Gm work done = mass r U = r −GMm · Gravitational Potential Energy Vg = · Gravitational potential I= · Gravitational field Intensity (iii) Law of Periods: T ∝a where, a = length of semi-major axis dt = F= Gm1 m2 , G = 6.67 ×10−11 Nm2 kg −2 r2 (i) (ii) (iii) (iv) el ne ss (g ) vorb= gR = 2 gR (iii) with rotation of earth about its own axis g’=g– Rω 2 cos 2 λ , 0 At poles, λ = 90 , g maximum 0 At equator, λ = 0 , g minimum i.e. g decreases with depth g′ = g 1− d , RE 2h g ′= g 1 − , RE i.e. g decreases with height R2e G Me with height g = Acceleration possessed by an object during free fall due to earth’s gravitational pull, During free fall under gravity inside a spacecraft or satellite a body is weightless i.e., effective weight becomes zero. 2 ve 2 GM / R 1 Mm GMm − GMm = + =– G 2r r 2 r E = K.E +P.E Total Energy of a satellite Orbitals speed (ii) with depth (i) gra vit y Weakest force in Nature. Central as well as conservative. Always attractive in nature. Applicable for all bodies irrespective of their shape, size and position. fo rc e Acceleratio n du e to Cha ract eris tics of gr av ita tio na l w of Ne a w l to Gravitation When two mass bodies are separted by a distance, they experience an attractive force which is directly proportional to the product of their masses and inversaly proportional to the square of their separation. l na tio a t tial ten o dp an d l Fie motion w- of planetary er ’s La Kepl Sat lit Heavenly object that revolves around a planet = v esc = Earth ’s v esc = 11.2km/s Escape speed Chapter - 8 ss dA (i) Law of Orbit: Every planet revolves around the Sun in an elliptical orbit and Sun is at its one focus. (ii) Law of Area: The radius vector drawn from the Sun to a planet sweeps out equal areas in equal intervals of time. Geostationary satellite Polar satellite Height from earth’s surface = 880km Time period = 84min Orbital velocity = 7.92km/s e Height from surface of earth =36000km Radius of orbit = 42,400km Time periods = 24 hours Orbital velocity = 3.1km/s Mind map : learning made simple tl e Gr av i W h eig n’ G s un ra i v it a v e r s a tio l n 8 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI Deforming force applied normal Fn = A Area Force Changing Volume FV = A Area pe longitudinal stress F / A = longitudinal strain l / ∆l F ∆l Mg∆l = π r 2l Al Y = Y = Young’s modulus of elasticity Property of material by virtue of which it regains it original shape & size after the removal of deforming force Stress 9 1 3 9 Bη = + or Y = Y B η η +3B (iv) E s Modulus Young’ Restoring force per unit area i.e., stress= AF s (iii) Shearing area or tangential stress Tangential Force F = = t A Area = (ii) Volumetric stress = (i) Longitudinal stress σ= (iii) 3B − 2 η 2η + 6B Relation between Y, B, η & σ (i) Y=3B (1 − 2 σ) Y=2η (1 + σ) (ii) Mechanical Properties of Solids Elasticity Elastic potential energy in a stretched 1 wire= ×stress × strain × volume of the wire 2 Ty ∆P 1 B=− ; = compressibility ∆V B V hydraulic stress B= volume strain Bulk modulus or volume modulus of elasticity Bulk Modulus Types of Modulus of Elasticity Within the elastic limit, stress is directly proportional to strain. i.e., stress ∝ strain Hooke’s law V change in length ∆l = original length lo o in volume ∆V = ε = change original volume V = Shearing strain=angular displacement of the plane perpendicular to the fixed surface = θ Volumetric strain Longitudinal strain T η= η= σs F F = A = εs θ Aθ tangential stress shearing strain Rigidity or shear modulus of elasticity Ratio of change in configuration to original configuration change in configuration Strain = original configuration Modulus of Rigid ity Strain (iii) (ii) (i) Laternal strain (β) ∆d / d = Longitudinal strain (α ) ∆l / l Value of σ lies between 0 and 0.5 Poision’s ratio(σ) = Chapter - 9 es rgy ne e l tia ten o cP sti la yp Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 9 2 1 2 2 2hρm g ρ (a 2 – a 2 ) of continuity m=a1v1ρ1=a2v2ρ2 for an incompressible liquid, ρ1=ρ2 then a1v1=a2v2 or av=constant Pascal’s law : The pressure exerted at any point on an enclosed liquid is transmitted equally in all direction. Hydraulic brakes and hydraulic lifts are based on Pacal’s law. Equation Fl Ven turim eter Applications ow of fl u ( ) ∆E ∆A = That can flow like liquids and gases Mechanical Properties of fluids Form u Vi P) solu s te P res ur e( Total or actual pressure at a point. Absolute pressure= atmospheric pressure + gauge pressure G a lae it y Difference between the absolute pressure at a point and the atmospheric pressure. Pg=absolute pressure(P) – atmospheric pressure(Pa) density of substance density of water at 4oC Density of water at 4°C i.e., maximum density of water=1.0×103 kg/m3 Volume(v) Density(ρ)= Mass(m) F tension S= l work done in increasing area W Surface Energy= = increase in surfacearea ∆A 2S cosθ Capillary rise or fall, h= r ρg Excess Pressure inside a drop (liquid) 2S Pexcess = R Excess Pressure inside a bubble (soap) 4S Pexcess = R Stroke’s law F=6 ηvr Opposing force between different layers of fluid in relative motion Viscous drag F= −ηA dv dx η=coefficient of viscosity Lift of an aircraft wing. Sprayer or atomizer Blowing off the roofs during windstorm. Surface o o o Chapter - 10 Relative Density or specific gravity= ) (Pg re su s re eP g u Pressure (atm) exerted by the atmosphere. At sea level, 1 atm=pressure exerted by 0.76m of Hg=hρg=0.76×13.6×103×9.8=1.013×105 Nm-2 =101.3kPa Pa) re( u s es Pr ic r he Pressure(P) = thrust(F) = ∆lim A→ 0 dF area(A) dA Pressure exerted by a liquid column of height h, (p)=hρg ids s s co For an incompressible non-viscous streamline,irrotational flow of fluid, 1 P + ρ v 2 + ρ gh = constant 2 uids of Fl s w La 1 2 Streamline : In liquid flow when the Velocity is less than critical velocity, each particle of the liquid passing through a point travels along the same path and same velocity as the preceding particles. Turbulent : When velocity of liquid flow is greater than critical velocity and particles follow zig-zag path. Q = a 1a2 Velocity of efflux of liquid through an orifice V = 2 gh To ric ell’s Device used to measure the rate of flow of liquid. Volume of liquid flowing per second Mind map : learning made simple Law Ab At m os p Bernoulli’s principle 10 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 1 or λ m = b 4 4 ) Stefan’s Boltzmann law Wien disp lac em en t la w Kr ich of Tempera t ure α= L – l0 ∆l = l0 ∆Τ l0(T – T0) a n l co Thermal Properties of Matter T h er m ng oli co f o law n’s o t New Types (In solids) Increase in dimensions due to increase in temperature d Pri nci ple of A – A0 ∆A dA β= = = A ∆ T A dT A0(T–T0) Increase in area of a solid on heating. Coefficient of superficial expansion or a:b:γ=1:2:3 γ=2β=3a Speci fic H ea t ∆T ∆Q calo rime try s ∆Q = n n∆ T V0 ∆T dV V0 dT γ = ∆V = = V – V0 V0(T – T0) Increase in volume of a solid on heating. Coefficient of cubical expansion. ∆F ∆l = Y , Y = Young’s modulus A l Heat lost = Heat Gain Molar specific heat capacity, c = Heat capacity s = s Q Specific heat capacity C = m= m∆T A form of energy, transferred between two systems by virtue of temperature difference. t 5 For water, latent heat of fusion, L f = 3.33× 10 J / kg 5 Latent heat of vapourisation, Lv = 22.6 × 10 J / kg Cubical or vo lum e ex pan Re lat sio ion n t ea H Chapter - 11 Heat required to change the state of unit mass substance without changing its temperature , L = Q m Q. x (K) = A( T2 − T1 ) t For small temperature difference between a body and its surroundings, the loss of dQ heat is given by − = k ( T2 − T1 ) dt Increase of length of a solid on heating. Coefficient of linear expansion TC − 0 T − 32 TK − 273.15 –0 = F = – =R 100 − 0 212 − 32 373.15 − 273.15 80 – 0 Relation among different temperature scales Degree of hotness or coldness of a body measuring device = Thermometer (i) Conduction : heat transfer through molecular collisions without any actual motion of matter. (ii) Convection : heat transfer by actual motion of matter within the medium. Land breeze, sea breeze, trade winds based on natural convection are some examples. (iii) Radiation : method of heat transfer requiring no material medium. E = σ T −T0 ( For a perfectly black body σ = 5.672 Js −1 m−2 k−4 E∝T 4 ; E = σ T 4 T T −3 b(wine’s constant) = 2.9 ×10 mK λm law Th e r m Expan al sion eλ aλ = Eλ = constant al erm Th aws L Superficial or area Expansion it y tiv uc f ’s La ten t H ea At any given temperature Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 11 Two systems are in thermal equilibrium with each other if they have the same temperature. Heat Engine V1 ∫ V2 nRT dv V W Q T Efficiency η= =1– 2 = 1– 2 QT1 Q T1 Converts continuously heat into mechanical energy in cyclic process. W = P γ T n- γ =Constant; PV = Constant γ −1 TV = Constant γ =γ Cv Cp Refrigerator and heat pump V1 V2 = T1 T2 = Constant P1 P2 = T1 T2 V CP =γ CV Mayer’s Equation CP −C =R v V β = W Q2 = = Q1 - Q 2 Q2 2 T1 - T T2 Refrigerator is a heat engine working in the reverse direction. Coefficient of performance, The pressure (P) & temperature (T) of the environment can differ from those of the system only infinitesimally. In this process, system returns to initial state for a cyclic process ∆U = 0 (zero) Pressure = Constant T Isochoric Process Volume = Constant P = Constant T Infinity slow process such that systems remain in thermal & mechanical equilibrium with the surroundings throughout. process i-static Quas Cycli c Pr oce ss cess Pro c i ar ob A thermally insulated system neither gains nor loses heat Is Branch of Science which deals with concepts of heat & temperature and their interconversion by thermodynamic process Thermodynamics capacity Rela tion ific heat Spec Property Temperature = Constant PV= Constant = n RT Efficiency of Carnot’s engine Q T η= 1 – 2 = 1 – 2 Q1 T2 An Ideal engine works on a reversible cycle of four operations in succession. (i) isothermal expansion , (ii) adiabatic expansion, (iii) isothermal compression, (iv)adiabatic compression. It is the statement of law of conservation of It is impossible for an engine working between Energy; ∆Q = ∆U + ∆W = ∆U+P∆U (Here, ∆U=P∆U) a cyclic process to extract heat from a reservoir and convert completely into work. Chapter - 12 If two systems A&B are in thermal equilibrium ics with a third system C, then A&B are in thermal am n equilibrium with each other. w y od t la y rm Zer irs e d F h o oth Measure of molecular disorder of a system. ft The Law rm wo δQ of rmo the econd la Change in entropy δ S = dyna S mics Laws T Thermo dyna mic state v ariab le n of a m ics (i) Extensive – indicate the size of the system. e.g. U, volume, total mass. (ii) Intensive – do not indicate size of the system. e.g. , pressure & temperature ot’ Engine Carn ersible & Irreversibl Rev e Pr oce Any process made to proceed in the ss reverse direction by changing its conditions is called Reversible Process. Any process which cannot be retraced in the reverse direction exactly is called Irreversible Process. quilibrium rmal E The Mind map : learning made simple py (S) Entro I s o t her ma l P ro ce ss Adiabati c P roc ess 12 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI = 3PV 3P 3 RT = = ρ M M Cv Cp 5 3 =γ= (4 + f) (3 + f ) De g re Energy associated with each degree of freedom per molecule = 1 kT 2 Pa th d om Fr ee fre e M ea n e of (f) and Ki ne ti c Ene y erg En Hence, f is the degree of freedom for polyatomic gases, for diatomic =γ= 7 =γ= Cv 5 Cp Cv Theor y of Gases Cp b rted λ= ) 2πnd 2 1 ssure ( P rgy (E) Re l ati on be twee n Pre s xe ee ur s y ga = 3 2 PV 1 2 P = ρV rms 3 Total pressure of a mixture of non - reacting gases, P = P1 + P2+...... +Pn 2 π d2 P kBT For polyatomic gas: (i)at room temperature, f = 6 (ii)at high temperature, f = 8 For monoatomic gas: f = 3 For diatomic gas : (i) at room temperature, f = 5 (ii) at high temperature, f = 7 E= e Dal ton’s Law of Parti al Pre ssur 1 V Chapter - 13 (If T = constant) PV = constant or P1V1=P2V2 P∝ es Pr ion rtit a ip qu for monoatomic Kinetic Theory Ass ump tion of Kinetic • All the molecules of a gas are identical. • The molecules of different gases are different. • The molecules of gases are in a state of random motion. • The collisions of gases molecules are perfectly elastic. ea cH i f i c Spe e ed y cit pa a tC Sp eed E of Specific Heat Capacity for an ideal gas, Cp– Cv = R vmp = are Sp bl e ob a r p t s qu s Mo Root me a n w La 2 RT 2 = = 0.816 vrms 3 vrms M va v = 8 RT = 8 vrms = 0.92 v rms π M 3π v + v2 + v3 + ... + vN va v = 1 N rms v w La e’s l y Bo An ideal gas satisfies equation PV = nRT at all pressure and temperature n = no. of moles, R = NAkB universal gas constant Behaviour Under the same condition of temperature and pressure equal volumes of all gases contain equal no. of molecules. i.e. N1= N2 Gu yL us sac ’s La w V ∝ T (If P = constant) V = constant T V1 V 2 or = T1 T2 Charles’s Law of Gases P ∝ T (If V = constant) P = constant T P P or 1 = 2 T1 T2 Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 13 Frequency F = spring constant x Damping force Fd= –bv, b = damping constant -(b/2m)t x = xme Amplitude decreases with time as x = xme-bt/2m sin(ωt+φ) m lace Disp e g sprin to a e u ns d atio l l i c Os ns io at n SH O sc illa tio ns 2 2 Fo 2 2 d 2 2 d {m (ω − ω ) +ω b } −vo tanφ = ωd xo Amplitude, A = Displacement, x (t)=Acos (ωd +φ) 1 2 Every oscillatory motion is periodic, but every periodic motion need not be oscillatory. To and fro motion repeatedly about a fixed point in a definite interval of time. Driving force, F (t) = Fo cosωd t Oscillations i nt E Velocity in SHM A= Amplitude i.e.,maximum displacement of particles. d Displacement of damped oscillator Phase Simple Harmonic Motion is The smallest interval of time T ) im e the simplest form of p eri o d ( T after which the motion oscillatory motion is repeated Time varying quantity ( ωt + φ ) ce Oscillation of a body whose amplitude goes on decreasing with time. Here, k = m k I l =2 π mgl g Time period T =2 π Time period T = 2 π The number of oscillations per second i.e., 1 ω f= = T 2π x(t)= A(cosωt+φ) Chapter - 14(a) M Phase constant or Phase angle (φ) It depends upon velocity ( v) and displacement of particle at t = 0 Mind map : learning made simple Fo r D a mp ed a= dv =−ω 2A cos (ωt +φ) dt a max= ω 2 A dx = – ωA sin(ωt+φ ) d (t ) vmax = ωA v= = When frequency of external force is equal to natural frequency of oscillator. ∴ω= k m F= −k ( x) , k = mω2 Force law equation for SHM 1 kA2 cos 2 ( ωt+ φ) + sin2 ( ωt +φ) 2 Potential Energy 1 P.E = mω 2 A2 cos2 (ωt +φ) 2 Total energy, T.E.=K.E.+ P.E. Kinetic Energy 1 K.E = mω2A2 sin2 (ωt + ϕ) 2 HM in S y rg ne O sc ill SHM 14 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 2l m v 2l at io n (iii) In open organ pipe, higher harmonics, both odd & even. In closed organ pipe, higher harmonics, odd only. 4l (b) Closed at one end ν = v Fundamental freq. or I harmonic ν = (ii) In organ pipe: (a) Open at both ends, (i) In string: Fundamental Frequency, ν = 1 T Stationary waves Waves associated with particles like-electrons, protons, neutrons, atoms, molecules etc. tter Ma po When two or more waves are Principle of super propagating with different s displacements then the net o f w a ve displacement of collective wave is given as Y = y1 + y2 + y3+.....+yn ves Wa on siti ar y Waves 1 Frequency Wave number, v = Types Do not require any material medium for their propagation e.g., light waves Mech anic al W ave s Waves 1 λ ) V = er s in a it u d Long s wave l √ Individual particles of the medium oscillate along the direction of propagation of wave. Individual particles of the medium oscillate perpendicular to the direction of propagation of wave T = tension & M = mass/length √ √ √ Speed of a longitudinal wave speed of sound, V = B ρ Y P γP = for air, γ = 7/5 ρ = ρ = ρ Require material medium for their propagation v ns Tra √ mT , Speed of transverse wave in a stretched string Difference in frequencies of two superposing waves, νbeat= ν1∼ ν2 ( ( t)) = A sin (–kx + t) ωφ y (x, y (x,t) = Asin 2 π t – x T λ ( ) amplitude Velocity v0=Aω2 Acceleration Amplitude a0 = Aω2 Essential properties for propagation Elasticity Inertia Minimum friction la re e t iv en m ress ce a g l o ts sp pr Di Bea wavelength 1 = 1 = ν Angular Frequency (ω) = 2 πν v = νλ Time period (T) = t n io leng t a l e Re wav ν ± νs ± νm n1 = n ν ± ν0 ± νm Here, v = speed of sound, v0 = observer speed vs = source speed vm = medium speed General Formula, Apparent Frequency Electromagnetic Waves e la n tio w n in av ap e Properties b/ w h wa (λ ve ) & v elo fre c it y q u e n c ( v), y (ν) Chapter - 14(b) e St es po av Do ct fe Ef r le w Mind map : learning made simple OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI 15 sin ( δmin + A ) / 2 Ray Optics MP =– fo & L = fo + fe fe When image is at D f f MP = − o 1 + e fe– D f & L = f o+ e f D + e Magnifying Power (MP) When image is at ∞ Telescope D v D L MP = − 1 + = 1 + fe u fe fo n bi m o C through light f o ion ers Prism sp i D Optical Instr um ent Tota l In ter na lR ef le ct Astronomical Magnifying Power (MP) When image is at ∞ vD MP = − & L = u + fe u fe When image is at D P= 1 f 1 1 1 = + f f1 f2 P = P1 + P2 sin A / 2 δ = A (µ −1) µ = δ=i+e−A A = r1 + r2 • Compound microscope • Astronomical microscope • Newtonian Telescope The complete reflection of a light ray reaching an interface with a less dense medium when the angle of incidence exceeds the critical angle. & ws La R 2 1 n2 = − 1 f n1 1 1 − R R 2 1 Mirror formula ⇒ 1 1 1 = + f v u I −v f f −v (2) Linear magnification, m = = = − O u f−u f (1) Focal length f = The separation of visible light into its different colours. δred < δviolet because ηred < ηviolet (ii) Angular dispersion : θ = δv – δr=(ηv – ηr )A δ − δr (iii) Dispersive power : ω = v δr When beam of light goes from one medium to another medium, it deviates from its path, such deviation of light in called refraction of light. Laws : (i) Incident ray, refracted ray & normal lie in the same plane. sin i (ii) Snell’s Law, refractive index (η) = sin r Sphe rica lM irr ors Fo rm ul a Chapter - 15 When beam of incident light bounces in the same medium. Laws : (i) Incident ray, reflected ray and normal lie in the same plane. (ii) Angle of incidence (∠ i) = Angle of reflection (∠ r) Dispersion of light n io ct a r f Re f l ec tio n & La w s Mind map : learning made simple at io C n o of m an th po in d u p n l en dM ow se er ic s r o sco pe n io Re 16 OSWAAL CBSE Chapterwise Mind Maps, PHYSICS, Class - XI er ak M s n’ Le