Loading documents preview...
SYSTEM OF PARTICLES AND ROTATIONAL MOTION
CLASS XI
Centre of Mass and Centre of Gravity l
l
Rotational Motion
The centre of gravity of a body coincides with its centre of mass only if the gravitational field does not vary from one point of the body to other.
l
Mathematically,
l
Perpendicular distance of each particle remains constant from a fixed line or point and particle do not move parallel to the line. Angular displacement, q =
R
R
l
For discrete body,
For continuous body,
Centre of mass of symmetric body w
l
Equations of rotational motion w w = w0 + at w
q = w0t + at 2
w
w 2 = w02 + 2aq
R
Torque : Turning effect of the force about the axis of rotation.
Axis R1
l
Semi-circular disc,
R2
Angular momentum, Work done by torque, W = tdq Power, P = tw Axis
Motion of Centre of Mass l
For a rigid body,
w
Position,
l
w
Velocity,
Perpendicular axes theorem : Iz = Ix + Iy (Object is in x-y plane )
2R
2R
z
y
Spherical shell
Solid sphere
x
Axis A
w
l
Acceleration, If
= 0, then
(for isolated system)
CM
a
d
= constant.
If the net external torque acting on a system is zero, the angular momentum of the system remains constant, no matter what changes take place within the system. = constant; I1w1 = I2w2
Parallel axes theorem : IAB = ICM + Md 2
Axis
R b
2
B
Conservation of Angular Momentum l
Axis
Moment of Inertia
For a system of particles
w
L
R
L
L
l
l
Axis
Axis
Semi-circular ring, l
w
Axis
Angular acceleration, a = l
w
Axis
I = MR2
Angular velocity, w = w
Axis
Rolling Motion
Equilibrium of a Rigid Body l
l
A rigid body is said to be in mechanical equilibrium, if both of its linear momentum and angular momentum are not changing with time, i.e., total force and total torque are zero. Linear momentum does not change implies the condition for the translational equilibrium of the body and angular momentum does not change implies the condition for the rotational equilibrium of the body.
I = MR /2
l
For a body rolling without slipping, velocity of centre of mass vCM = Rw Kinetic energy, K = Ktranslational + Krotational =
GRAVITATION $-"449* /FXUPOT-BXPG(SBWJUBUJPO (SBWJUBUJPOBM GPSDF ' CFUXFFO UXP CPEJFT JT EJSFDUMZ QSPQPSUJPOBM UP QSPEVDU PG NBTTFT BOE JOWFSTFMZ QSPQPSUJPOBMUPTRVBSFPGUIFEJTUBODFCFUXFFOUIFN
-BXPGPSCJUT&WFSZQMBOFUSFWPMWFT BSPVOEUIFTVOJOBOFMMJQUJDBMPSCJU BOEUIFTVOJTTJUVBUFE BU POFPG JUT GPDJ
,FQMFST-BXTPG 1MBOFUBSZ.PUJPO
-BXPGBSFBT5IFBSFBMWFMPDJUZPG UIFQMBOFUBSPVOEUIFTVOJTDPOTUBOU JF
"DDFMFSBUJPOEVFUPHSBWJUZ 'PSBCPEZGBMMJOHGSFFMZVOEFS HSBWJUZ UIFBDDFMFSBUJPOJOUIF CPEZ JT DBMMFE BDDFMFSBUJPO EVFUPHSBWJUZ 3FMBUJPOTIJQCFUXFFOHBOE(
XIFSF(HSBWJUBUJPOBMDPOTUBOU ρEFOTJUZPGFBSUI .FBOE3FCFUIFNBTTBOESBEJVT PGFBSUI
$IBSBDUFSJTUJDT PGHSBWJUBUJPOBMGPSDF *UJTBMXBZTBUUSBDUJWF *UJTJOEFQFOEFOUPGUIFNFEJVN *UJTBDPOTFSWBUJWFBOEDFOUSBMGPSDF *UIPMETHPPEPWFSBXJEFSBOHFPG EJTUBODF
-BXPGQFSJPET5IFTRVBSFPGUIFUJNFQFSJPEPG SFWPMVUJPOPGBQMBOFUJTEJSFDUMZQSPQPSUJPOBMUP UIFDVCFPGTFNJNBKPSBYJTPGUIFFMMJQUJDBMPSCJU 5∝B
(SBWJUBUJPOBM1PUFOUJBM&OFSHZ 8PSLEPOFJOCSJOHJOHUIFHJWFOCPEZGSPN JOGJOJUZUPBQPJOUJOUIFHSBWJUBUJPOBMGJFME 6o(.NS
(SBWJUBUJPOBMQPUFOUJBM 8PSLEPOFJOCSJOHJOHBVOJUNBTTGSPN JOGJOJUZ UP B QPJOU JO UIF HSBWJUBUJPOBM GJFME
7BSJBUJPOPGBDDFMFSBUJPO EVFUPHSBWJUZ H
%VFUPBMUJUVEF I
5ZQFTPG4BUFMMJUF
&TDBQFTQFFE 5IFNJOJNVNTQFFEPGQSPKFDUJPOPGB CPEZGSPNTVSGBDFPGFBSUITPUIBUJUKVTU DSPTTFTUIFHSBWJUBUJPOBMGJFMEPGFBSUI
&BSUIT 4BUFMMJUF
5JNFQFSJPEPGTBUFMMJUF 5IFWBMVFPGHHPFTPO EFDSFBTJOHXJUIIFJHIU %VFUPEFQUI E
5IFWBMVFPGHEFDSFBTFT XJUIEFQUI %VFUPSPUBUJPOPGFBSUI HλHo3FωDPTλ "UFRVBUPS λ¡ HλNJOHo3Fω "UQPMFT λ¡ HλNBYHQH
1PMBSTBUFMMJMUF 5JNFQFSJPENJO 3FWPMWFT JO QPMBS PSCJU BSPVOEUIFFBSUI )FJHIULN 6TFT8FBUIFSGPSFDBTUJOH NJMJUBSZTQZJOH (FPTUBUJPOBSZTBUFMMJUF 5JNFQFSJPEIPVST 4BNF BOHVMBS TQFFE JO TBNF EJSFDUJPO XJUI FBSUI )FJHIULN 6TFT(14 TBUFMMJUF DPNNVOJDBUJPO 57
'PS TBUFMMJUF PSCJUJOH DMPTF UP UIF FBSUITTVSGBDF
0SCJUBMTQFFEPG TBUFMMJUF 5IF NJOJNVN TQFFE S F R V J S F E U P Q V U U I F TBUFMMJUFJOUPBHJWFOPSCJU
'PSTBUFMMJUFPSCJUJOHDMPTF UPUIFFBSUITTVSGBDF
&OFSHZPGTBUFMMJUF
,JOFUJDFOFSHZ
1PUFOUJBMFOFSHZ
5PUBMFOFSHZ
MECHANICAL PROPERTIES OF SOLIDS AND FLUIDS CLASS XI RELATION BETWEEN Y, B, G AND s l Y = 3B(1 –2s) l Y = 2G(1 +s)
Young’s modulus Bulk modulus,
APPLICATION OF ELASTICITY Designing beams for bridges The depression in rectangular
l
l
beam,
Compressibility, k = 1/B
l
ELASTIC POTENTIAL ENERGY HOOKE’S LAW
Modulus of rigidity
Stress µ Strain or Stress = E ´ Strain, (E = modulus of elasticity)
P.E. stored per unit volume of stretched wire,
Poisson’s ratio s
ELASTICITY AND PLASTICITY STRESS AND STRAIN l
l
VISCOSITY Coefficient of viscosity: where
is the velocity
gradient between two layers of liquid.
BERNOULLI’S THEOREM Bernoulli’s theorem : For the streamline flow of an ideal liquid, the total energy per unit volume remains constant
Stoke’s law : Backward dragging force on a spherical body, F = 6 phrv.
Basic results on viscosity
PROPERTIES OF SOLIDS PROPERTIES OF FLUIDS FLUIDS IN MOTION
FLUIDS AT REST
PRESSURE Pascal’s law The pressure is same at all points inside the liquid lying at the same depth in a horizontal plane. Gauge pressure = P – P0 = hrg. ARCHIMEDE’S PRINCIPLE
Reynold’s number : Determines
When a body is immersed fully or partly in a liquid at rest, it loses some of its weight, which is equal to the weight of the liquid displaced by the immersed part of the body.
nature of fluid flow
Apparent weight
Poiseuille’s formula
(For fully immersed body)
Elasticity : Ability of a body to regain its original shape, on removing deforming force. Plasticity : The inability of a body to regain its original size and shape on the removal of the deforming forces.
SURFACE TENSION Surface tension: The property by which the free surface of liquid at rest tends to have minimum surface area. Surface energy: Work done against the force of surface tension in forming the liquid surface.
CAPILLARITY The phenomenon of rise or fall of liquid in a capillary tube is called capillarity. Height of the liquid within capillary tube Where, q = angle of contact r = density of liquid a = radius of tube
In an air bubble
Excess Pressure
Inside a soap bubble
Inside a liquid drop
0
1
273
SHM IN SPRING
FORCE LAW IN SHM
GENERAL EQUATIONS OF SHM
DAMPED AND FORCED OSCILLATIONS
SIMPLE PENDULUM
ENERGY IN SHM
ELECTRIC FLUX
ELECTROMAGNETIC INDUCTION
CLASS XII
Combination of Inductors
Magnetic Energy l
l
Energy stored in an inductor,
l
Inductors in series,
l
Inductors in parallel,
l
If coils are far away, then M = 0.
Energy stored in the solenoid,
L–R Circuit l Current growth in L–R circuit l
So,
Current decay in L–R circuit, Here,
l
Magnetic energy density,
Inductance
Lenz's Law l
l
l
The direction of the induced current is such that it opposes the change that has produced it. If a current is induced by an increasing(decreasing) flux, it will weaken (strengthen) the original flux. It is a consequence of the law of conservation of energy.
l
Emf induced in the coil/conductor,
l
Coefficient of self induction,
l
Self inductance of a long solenoid,
l
Mutual inductance,
l
Mutual inductance of two long coaxial solenoids,
l
Induced Electric Field l
It is produced by change in magnetic field in a region. This is non-conservative in nature.
l
This is also known as integral form of Faraday’s law.
Coefficient of coupling, For perfect coupling, k = 1 so,
Magnetic Flux and Faraday's Law l l
Energy Consideration in Motional emf l
Emf in the wire, e = Bvl
l
Induced current,
l
Force exerted on the wire,
Magnetic flux Faraday’s law : Whenever magnetic flux linked with a coil changes, an emf is induced in the coil. w
Induced emf,
w
Induced current,
w
Induced charge flow ,
Electric Generator l
I l
B ×
v
F
R l
Motional emf
Power required to move the l
wire, It is dissipated as Joule’s heat.
l
On a straight conducting wire, e = Bvl On a rotating conducting wire about one end, Here,
are perpendicular to each other.
l
l
Mechanical energ y is converted into electrical energy by virtue of electromagnetic induction. Induced emf, e = NABw sinwt = e0sinwt Induced current,
ALTERNATING CURRENT ELECTROMAGNETIC WAVES $-"449** ε
π/2
π
3π/2
)BMGDZDMF oε
"MUFSOBUJOH$VSSFOU
"$WPMUBHF
$VSSFOUXIJDIDIBOHFTDPOUJOVPVTMZJO NBHOJUVEFBOEQFSJPEJDBMMZJOEJSFDUJPO
2π ωU
0OFGVMMDZDMF
"MUFSOBUJOHWPMUBHF εεTJOωU
"QQMJFEBDSPTT DBQBDJUPS
1VSFMZSFTJTUJWFDJSDVJU
5SBOTGPSNFSSBUJPT
&GGJDJFODZPGBUSBOTGPSNFS
"QQMJFEBDSPTT JOEVDUPS
"QQMJFEBDSPTTSFTJTUPS
1VSFMZDBQBDJUJWFDJSDVJU $VSSFOU MFBET UIF WPMUBHF CZ B QIBTFBOHMFPGπ
5SBOTGPSNFS
1VSFMZJOEVDUJWFDJSDVJU $VSSFOUMBHTCFIJOEUIFWPMUBHFCZB QIBTFBOHMFPGπ
**TJO ωU π
"MUFSOBUJOH WPMUBHF JT JO QIBTFXJUIDVSSFOU
**TJO ωUoπ *ε9-εω-
XIFSF9$ω$
*ε3*TJOωU
XIFSF9-ω-
4UFQVQUSBOTGPSNFS ε4ε1 *4*1BOE/4/1 4UFQEPXOUSBOTGPSNFS ε4ε1 *4*1BOE/4/1
$PNCJOJOH-$3JOTFSJFT 1PXFSJOBDDJSDVJU "WFSBHFQPXFS 1BW
1PXFSGBDUPS
1PXFSGBDUPS
*OQVSFSFTJTUJWFDJSDVJU φ¡DPTφ *OQVSFMZJOEVDUJWFPS DBQBDJUJWFDJSDVJU
4FSJFT-$3DJSDVJU εεTJOωU **TJO ωUoφ
*NQFEBODFPGUIFDJSDVJU 1IBTFEJGGFSFODFCFUXFFODVSSFOUBOEWPMUBHFJTφ
'PS9-9$ φJT WF 1SFEPNJOBOUMZJOEVDUJWF
'PS9-9$ φJToWF 1SFEPNJOBOUMZDBQBDJUJWF
.BHOFUJD GJFME
&OFSHZEFOTJUZPG FMFDUSPNBHOFUJDXBWFT "WFSBHFFOFSHZEFOTJUZ
&MFDUSJD GJFME 1SPQBHBUJPO EJSFDUJPO
2VBMJUZGBDUPS *U JT B NFBTVSF PG TIBSQOFTT PG SFTPOBODF
%JTQMBDFNFOUDVSSFOU %JTQMBDFNFOU DVSSFOU BSJTFT XIFSFWFS UIF FMFDUSJDGMVYJTDIBOHJOHXJUIUJNF *%ε Eφ&EU
.BYXFMMhTFRVBUJPOT (BVTThTMBXGPSFMFDUSPTUBUJDT
8BWFMFOHUI λ
1SPEVDUJPOPGFMFDUSPNBHOFUJDXBWFT
XBWF
3FTPOBOUGSFRVFODZ
&MFDUSPNBHOFUJD8BWFT 8BWFTIBWJOHTJOVTPJEBMWBSJBUJPOPG FMFDUSJDBOENBHOFUJDGJFMEBUSJHIU BOHMFTUPFBDIPUIFSBOEQFSQFOEJDVMBS UPEJSFDUJPOPGXBWFTQSPQBHBUJPO
*OTFSJFT-$3DJSDVJU "USFTPOBODF 9-9$ ∴ ;3BOEφ¡ DPTφ
*OUFOTJUZ PG FMFDUSPNBHOFUJD
3FTPOBOUTFSJFT-$3DJSDVJU 8IFO9-9$ ;3 DVSSFOU CFDPNFTNBYJNVN
5ISPVHIBDDFMFSBUJOHDIBSHF #ZIBSNPOJDBMMZPTDJMMBUJOHFMFDUSJDDIBSHFT 5ISPVHIPTDJMMBUJOHFMFDUSJDEJQPMFT
(BVTThTMBXGPSNBHOFUJTN
'BSBEBZhTMBXPGFMFDUSP NBHOFUJDJOEVDUJPO
.BYXFMM"NQFSFhT DJSDVJUBMMBX
RAY OPTICS AND OPTICAL INSTRUMENTS CLASS XII w w w w
APPLICATIONS OF TIR Fiber optics communication Medical endoscopy Periscope (Using prism) Sparkling of diamond
t ligh ible Vis
P Deviation of red light(dR) A (i– r1) (e– r 2) Deviation of d N2 N1 R violet light (dV) e i O r r q 1 2 F G Y G E N B H Angular I spread V Q R Screen
REFRACTION THROUGH PRISM TOTAL INTERNAL REFLECTION TIR conditions w Light must travel from denser to rarer. w Incident angle i > critical angle ic Relation between m and ic:
Relation between m and dm where, dm = angle of minimum deviation A = angle of prism
Snell’s law: When light travels from medium a
Power of lens :
f Combination of lenses: Power: P = P1 + P2 – dP1P2 (d = small separation between the lenses) For d = 0 (lenses in contact) Power: P = P1 + P2 + P3 + ...
THIN SPHERICAL LENS Thin lens formula :
or d = m – 1 A (Prism of small angle) Angular dispersion
f
Magnification:
= dV – dR = mV – mR A
REFRACTION OF LIGHT
POWER OF LENSES
Dispersive power,
REFRACTION BY SPHERICAL SURFACE
to medium b, Refractive index,
Mean deviation,
Relation between object distance (u), image distance (v) and refractive index (m) (Holds for any curved spherical surface.)
Real and apparent depth Lens maker’s formula f
REFLECTION OF LIGHT According to the laws of reflection, Ði = Ðr If a plane mirror is rotated by an angle q, the reflected rays rotates by an angle 2q.
SIMPLE MICROSCOPE Magnifying power For final image is formed at D
RAY OPTICS
Mirror formula,
OPTICAL INSTRUMENTS
(least distance)
REFLECTING TELESCOPE Magnifying power f f f
f
Magnification, m =
COMPOUND MICROSCOPE Magnifying power, M = mo × me For final image formed at D (least distance)
f For final image formed at infinity f
REFLECTION BY SPHERICAL MIRRORS
f
f
For final image formed at infinity
TELESCOPE
f
Astronomical telescope For final image formed at D (least f f distance) f In normal adjustment, image formed at infinity M = fo / fe
f
TERRESTRIAL TELESCOPE f For normal adjustment f Distance between objective and eyepiece d = fo + 4f + fe
Electron orbits and their energy
A. Fission
B. Fusion
EXTRINSIC SEMICONDUCTORS
JUNCTION TRANSISTOR
INTRINSIC SEMICONDUCTORS
SEMICONDUCTOR DIODE
BIASING CHARACTERSTICS APPLICATIONS OF DIODE APPLICATIONS OF TRANSISTOR
CE(n-p-n)
Amplifier