CLASS XII PHYSICS (042)

1 PHYSICS (042) / XII / TERM-1 /2021-22 KENDRIYA VIDYALAYA SANGATHAN AHMEDABAD REGION STUDY MATERIAL TERM-1 CLASS XII PHYSICS (042) Session 2021-22 PHYSICS (042) / XII / TERM-1 /2021-22 INSPIRATION Shri(Dr) Jaydeep Das Deputy Commissioner KVS RO Ahmedabad Smt Shruti Bhargava Assistant Commissioner KVS RO Ahmedabad MENTOR Shri Avijit Panda Principal Kendriya Vidyalaya,Sabarmati PHYSICS (042) / XII / TERM-1 /2021-22 CONTENT DEVELOPEMENT TEAM Name of Teacher Designation Name of KV 1 Mrs. Vandana Badola PGT PHYSICS SHAHIBAUG AHMEDABAD 2 Mr. R N Singh PGT PHYSICS SHAHIBAUG AHMEDABAD 3 Mr. Bhupesh Kumar Nagoda PGT PHYSICS AHMEDABAD CANTT 4 Mr. R H Parmar PGT PHYSICS SAC AHMEDABAD 5 Mr. M P Dabi PGT PHYSICS ONGC CHANDKHEDA 6 Mr. T C Agrawal PGT PHYSICS ONGC CHANDKHEDA 7 Mr. Gurmeet Singh PGT PHYSICS HIMMATNAGAR 8 Mrs.

2 Anju Kumari PGT PHYSICS AFS WADSAR 9 Mr. Praveen Nogia PGT PHYSICS BSF DANTIWADA 10 Mr. S K Devrani PGT PHYSICS SEC 30 GANDHINAGAR 11 Mr. Sandeep Kumar Koli PGT PHYSICS SEC 30 GANDHINAGAR 12 Mr. Bhoor Singh Meena PGT PHYSICS CANTT GANDHINAGAR 13 Mr. Shabbir Hingorja PGT PHYSICS CRPF GANDHINAGAR 14 Mrs. Anjana PGT PHYSICS NO 1 AFS BHUJ 15 Mr. Akhilesh Suryavanshi PGT PHYSICS NO 2 BHUJ CANTT 16 Mr. Deepak Kumar Singhal PGT PHYSICS AFS NALIYA 17 Mr. Viswanath PGT PHYSICS DHRANGADHRA 18 Mr. Yaksh Deep PGT PHYSICS PORBANDAR 19 Mr. Sahil Aneja PGT PHYSICS BHAVNAGAR PARA 20 Mr. Ranjay Kumar Sharma PGT PHYSICS RAJKOT 21 Mr. Om Prakash Yadav PGT PHYSICS RAJKOT 22 Mr. Mukesh Kumar PGT PHYSICS NO 1 AFS JAMNAGAR 23 Ms. Suryakant Vats PGT PHYSICS NO 1 AFS JAMNAGAR 24 Mr. Ram PGT PHYSICS INF LINES JAMNAGAR 25 Dr Neeraj Singh PGT PHYSICS AFS II JAMNAGAR 26 Mr. Umesh Kumar PGT PHYSICS INS VALSURA 27 Mr.

3 Pinkesh Rathod PGT PHYSICS AFS SAMANA 28 Mr. Naveen Kumar PGT PHYSICS DIU 29 Mr. Rakesh Kumar PGT PHYSICS NO 1 BARODA 30 Mr. S V Singh PGT PHYSICS EME BARODA 31 Mr. Sudhir Bhootda PGT PHYSICS EME BARODA 32 Mr. Sanjeev Chaddha PGT PHYSICS AFS BARODA 33 Mr. J K Jain PGT PHYSICS AFS BARODA 34 Mrs. Sangeeta Arora PGT PHYSICS ONGC BARODA 35 Mr. Chitresh Pandya PGT PHYSICS DAHOD 36 Mr. C M Sharma PGT PHYSICS ONGC ANKLESHWAR 37 Mr. V K Pathak PGT PHYSICS NO 1 SURAT 38 Mr. Pawan Kumar PGT PHYSICS KRIBHCO SURAT 39 Mr. R M Shukla PGT PHYSICS ONGC SURAT 40 Mr. A P Singh PGT PHYSICS SILVASSA 41 Mr. P K Sah PGT PHYSICS VV NAGAR 42 Mrs. Anju PGT PHYSICS ONGC MEHSANA 43 Mr. Kamlesh Kumar PGT PHYSICS RAILWAY GANDHIDHAM 44 Mr. Balwant Kumar PGT PHYSICS AHMEDABAD CANTT 45 Mr. Vikas Sharma PGT PHYSICS SABARMATI PHYSICS (042) / XII / TERM-1 /2021-22 PHYSICS CLASS -XII INDEX Particulars 1 SYLLABUS (TERM-1) 2 Deleted Topics (TERM-1) 3 question paper Design (TERM-1) 4 Chapter-1; Electric Charge and Field 5 Chapter-2; Electric Potential and Capacitance 6 Chapter-3; Current Electricity 7 Chapter-4; Moving Charges and Magnetism 8 Chapter-5; Magnetism and Matter 9 Chapter-6; Electromagnetic Induction 10 Chapter-7; Alternating Current 11 CBSE Sample paper (TERM-1) with Answer key 2021-22 *Every Chapter Contains: 1.

4 Gist of Lesson 2. Multiple Choice Questions with Answer key 3. Assertion and Reason question with Answer key 4. Case Study Based Questions with Answer key PHYSICS (042) / XII / TERM-1 /2021-22 SYLLABUS TERM-1 Session 2021-22 PHYSICS , CLASS -XII UNIT Chapters Marks Unit 1 Chapter 1: Electric Charges and Fields Chapter 2: Electric Potential and Capacitance 17 Unit 2 Chapter 3: Current Electricity Unit 3 Chapter 4: Moving Charges and Magnetism Chapter 5: Magnetism and Matter 18 Unit 4 Chapter 6: Electromagnetic Induction Chapter 7: Alternating Current Total 35 PHYSICS (042) / XII / TERM-1 /2021-22 DELETED TOPICS (For Session 2021-22) PHYSICS (042) CLASS XII TERM-1 Name of the Chapter Deleted Topics 1 Electric Charges & Fields uniformly charged thin spherical shell (field inside and outside).

5 2 Electric Potential & Capacitance No topic is deleted 3 Current Electricity Carbon resistors, colour code for carbon resistors; series and parallel combinations of resistors 4 Moving Charges and Magnetism Cyclotron 5 Magnetism and Matter magnetic field intensity due to a magnetic dipole (bar magnet) along its axis and perpendicular to its axis, torque on a magnetic dipole (bar magnet) in a uniform magnetic field; Para-, dia- and ferro - magnetic substances, with examples. Electromagnets and factors affecting their strengths, permanent magnets. 6 Electromagnetic Induction No topic is deleted 7 Alternating Current power factor, wattless current PHYSICS (042) / XII / TERM-1 /2021-22 question paper DESIGN TERM-1 EXAM 2021-22 CHAPTER 1 ELECTRIC CHARGE & FIELD GIST OF LESSON: Coulomb s Law of Electrostatics Electrostatic force of interaction acting between two stationary point charges is given by = 14 0.

6 1 2 2 where q1, q2 are magnitude of point charges, r is the distance between them and o is permittivity of free space. Here, 1 / 4 o = 9 x 10 9 N-m2/C2 The value of o is X 10-12 C2 / N-mC2. If there is another medium between the point charges except air or vacuum, then o is replaced by oK or o r or . where K or r is called dielectric constant or relative permittivity of the medium. K = r = / o where, = permittivity of the medium. For air or vacuum, K = 1 For water, K = 81 For metals, K = Coulomb Law implies: Force on q1 due to q2 = Force on q2 due to q1 F12 = F21 The forces due to two point charges are parallel to the line joining point charges; such forces are called central forces and electrostatic forces are conservative forces. Electric Field: The space in the surrounding of any charge in which its influence can be experienced by other charges is called electric field.

7 Electric Field Lines An electric field line is an imaginary line or curve drawn through a region of space so that its tangent at any point is in the direction of the electric field vector at that point. The relative closeness of the lines at some place give an idea about the intensity of electric field at that point. Two lines can never intersect. Electric field lines always begin on a positive charge and end on a negative charge and do not start or stop in mid space. Electric Field Intensity (E) The electrostatic force acting per unit positive charge on a point in electric field is called electric field intensity at that point. Electric field intensity = Its SI unit is NC-1 or V/m and its dimension is [MLT-3 A-1]. It is a vector quantity and its direction is in the direction of electrostatic force acting on positive charge. Electric field intensity due to a point Charge: due to a point charge q at a distance r is given by Magnitude - = 14 0.

8 2 Properties of Electric Field Lines: Electric lines of force are the imaginary lines drawn in electric field at Which a positive test charge will move if it is free to do so. Electric lines of force start from positive charge and terminate on negative charge. A tangent drawn at any point on electric field represents the direction of electric field at that point. Two electric lines of force never intersect each other. Electric lines of force are always perpendicular to an equipotential surface. Electric Flux ( E) Electric flux over an area is equal to the total number of electric field lines crossing this area. Electric flux through a small area element dS is given by E = E. dS where E= electric field intensity and dS = area vector. Its SI unit is Nm2C-1. Gauss s Theorem: The electric flux over any closed surface is 1 / o times the total charge enclosed by that surface, , =.

9 = 0 where Qin = Net Charge enclosed in the surface. Note: If a charge q is placed at the centre of a cube, then total electric flux linked with the whole cube = q / o, electric flux linked with one face of the cube = q / 6 o. Electric Field Intensity due to an Infinite Line Charge = 2 0 ( Direction Radially outwards for q > 0 and inwards or q<0) where is linear charge density and r is distance from the line charge. Electric Field Near an Infinite Plane Sheet of Charge: E = / 2 o where = surface charge density. If infinite plane sheet has uniform thickness, then E = / o Electric Dipole: An electric dipole consists of two point charges of equal magnitude and opposite sign separated by a very small distance. , a molecule of HCL, a molecule of water etc. Electric Dipole Moment p = q (2a) Its SI unit is coulomb-metre and its dimension is [LTA).]

10 It is a vector quantity and its direction is from negative charge towards positive charge. Electric Field Intensity and Potential due to an Electric Dipole (i) On Axial Line Electric field intensity = 14 2 ( 2 2)2 If r > > 2a, then = 14 2 3 ( Short Dipole) Electric potential = 14 2 2 If r > > 2a, then = 14 ( Short Dipole) (ii) On Equatorial Line Electric field intensity = 14 ( 2 + 2)3/2 If r > > 2a, then = 14 3 ( Short Dipole) Electric potential V = 0 (iii) At any Point along a Line Making Angle with Axis Electric field intensity = 14 1+3 2 3 Electric potential = 14 2 2 2 If r > > 2a, then = 14 2 ( Short Dipole) Torque: Torque acting on an electric dipole placed in uniform electric field is given by = pEsin or = p x E When = 90 , then max = pE (Maximum) When electric dipole is parallel to electric field, it is in stable equilibrium and when it is anti-parallel to electric field, it is in unstable equilibrium.