LEARNING OBJECTIVES BASED ON " BLOOM'S TAXONOMY "

CLASS : XII 

CBSE BOARD

Chapter – 1 : Electric Charges and Field

Learners would be able to

1. Characterize the properties of electric charge.

2. state Gauss’s Theorem and Superposition principle .

3. Formulate electric field due to an electric dipole at axial and equatorial point

4. Interpret the properties of electric field  of different types of charge distributions using electric field lines .

5. Derive the expression of electric field due to infinitely long straight wire , uniformly charged infinite plane sheet and uniformly charged thin spherical shell .

Chapter. – 2 Electric Potential and Capacitance .

Learners would be able to :

1. Distinguish between Electric Potential and potential difference .

2. Sketch equipotential surface due to different charge distribution .

3.   Deduce the electrical potential energy of a system of two point charges and of electric dipole   in an electrostatic field 

4.    Illustrate the principle behind construction of Capacitor .

5.  Describe the effect of using dielectric or conducting slab on the capacitance of a capacitor.

Chapter – 3 Current Electricity

Learners would be able to

1. State the principle of Meter Bridge , Potentiometer and Ohm’s law

2.  Describe the way of finding out internal resistance of a cell using Potentiometer .

3. Calculate the resistance of carbon resistors using colour code .

4.  Draw the circuit diagrams based on Potentiometer and Meter – Bridge .

5. Compare different types of materials based on electrical resistivity and conductivity value

6.  Describe the temperature dependence of resistance .

Chapter –4 : Magnetic Effects of Electric Current

Learners would be able to :

1.  Describe Oersted’s experiment leading to the discovery of Magnetic Effects of Electric Currentv .

2. State Ampere’s circuital and Biot – Savart ‘s law

3. Deduce magnetic field due to a straight current carrying wire and current carrying circular coil .

4.  Compare the force acting between two parallel current – carrying conductors when current flow through both the wires in same direction or in opposite direction .

5.  Explain the principle , construction and working of Cyclotron .

Chapter –5 : Magnetism and Matter

Learners would be able to 

1.  Calculate magnetic dipole moment of a revolving electron .

2. Compare the magnetic field intensity  due to a magnetic dipole along its axis and perpendicular to its axis.

3. iIllustrate bar magnet as an equivalent solenoid.

4.  Distinguish between para - , dia – and ferro – magnetic substances .

5. Describe earth’s magnetic field using magnetic elements .

Chapter – 6 : Electromagnetic Induction 

Learners would be able to :

1. Describe Faraday’s laws for explaining electromagnetic induction .

2.  Distinguish between Self Induction and Mutual Induction 

3. Experimentally show the concept of magnetic field .

4. Explain the law of conservation of energy 

Chapter – 7 : Alternating Current

Learners would be able to : 

1.  Distinguish between resistance , reactance and impedence .

2.   Describe peak and rms values of alternating current / voltage .

3. Deduce the expression of power in AC circuits.

4.  Define wattless current .

5. Explain the significance of Power factor .
   

Chapter – 8 : Electromagnetic Waves  

Learners would be able to :

1.   Explain the need for displacement current .

2.      Characterize the electromagnetic waves based on their wavelength and frequency 

3.        Describe the different  uses of em waves .

   
   

Chapter – 9 : Ray Optics 

Learners would be able to 

1. Write all the formulae related to Reflection of light through mirrors  refraction of light through lenses , lensmaker’s formula etc .

2.Explore the phenomenon of refraction of white light through Prism .

3.Explore the nature of image formed when object is placed at different positions of spherical  mirrors and lenses .

4.Construct telescope using convex mirror of different focal length and aperture .

5.Cite different real life examples pertaining to scattering of light .

6.Interpret the significance of various optics phenomenon like reflection , refraction , interference etc to explain the real life phenomenon .

7.Compare and contrast Interference and Diffraction .

Chapter – 10 : Wave Optics 

Learners would be able to

1. Deduce laws of refraction and reflection using Huygen’s Principle

2.  Compare and contrast Interference and Diffraction .

3.  Summarize conditions required for making an interference , diffraction and Polarization pattern.

4. Demonstrate experimentally the concept of Polarization of light using Polarization and Analyzer

5. Use different formulae related to Interference , Diffraction and Polarization for solving different numerical Problems .

6. State and formulate Brewster’s law , law of Malus etc .
   

   
   

Chapter – 11  Dual Nature of Radiation and Matter

Learners would be able

1.        State de – broglie hypothesis

2.        Interpret the significance of Davisson and Germer’s experiment to prove the wave nature of electron 

3.        Deduce the eavelength of electron moving in a potential difference of ‘V’ volt

4.        Conclude the observations of Frank and Hertz’s experiment based on Photoelectric effect .

5.        Make use of particle nature nature of electron to explain the observations of Frank and Hertz experiment 

6.        Prove that the wave nature of electron is irrelevant in explaining the observations of Frank and Hertz experiment .

Chapter – 12 : ATOMS

Learners would be able to

1. 1.   Postulates the observations of Rutherford’s “ Gold Foil Experiment 

2. 2. Compare different Atomic Models – Plum Pudding , Rutherford and Bohr Atomic 

3. 3. Identify the drawbacks of each Atomic Model  studied .
   

   
   
4.  Deduce the radius , velocity , Kinetic Energy , Potential Energy and Total Energy of a revolving electron based on Bohr’s Atomic Model .

Chapter - 13 : Nuclei

Learners would be able to 

1. describe the properties of Nuclei.

2. state Radioactive Decay law .

3. write the properties of alpha , beta and gamma rays .

Chapter - 14 Electronic Devices

Learners would be able to 

1. describe the principle , construction and working of devices like Rectifiers etc

2. differentiate between forward and reverse biasing .

3.   explain the formation of PN junction .

 

   Compact Disc (CD ) as Diffraction grating

Diffraction refers to various phenomena that occur when a wave encounters an obstacle or a slit .

Italian scientist Francesco Maria Grimaldi coined the word " Diffraction " and was the first to record accurate observations of the phenomenon in 1660 .It is defined as the bending of waves around the corners of an obstacle or through an aperture into the region of geometrical shadow of the obstacle/aperture.

Diffraction in CDs 

The development of compact disc involved a combination of laser Physics , Optics and Computer science . A CD consists of a series of alternating pits and and lands that spiral around the CD . When laser light is incident on a CD , the tracks of pits and lands cause the CD to behave as a diffraction grating . 

The pattern produced by the diffraction like phenomenon and the spacing of those pits and lands determines the amount of data on a CD .This distance between  adjacent tracks , commonly referred to as the track pitch .

Aim of the Experiment 

To 
1. demonstrate that CD has the characteristics of an optical grating .
2. find the grating constant or track pitch  of a CD
3. calculate the unknown wavelength of the laser .

Materials Required : 

Laser Pointer , Compact Disc , scissors , ruler ,protractor ,  pencil .

Theory : 

Diffraction (bending) of light is due to wave properties of light. It means that when a light wave encounters an obstacle, it does not propagate linearly behind the obstacle. During diffraction on an optical grating, formed by a system of a large number of parallel slits with equal width, a monochromatic light wave of a wavelength λ creates an interference pattern on a screen. The directions of interference amplification are determined by the angle θ, for which it applies

d (sinθ) = mλ

where d is the distance between two adjacent slits, called a grating constant or a grating period, and m = 0, 1, 2, … is the order of diffraction.

A recording on a CD is in the form of microscopic pits of different lengths that carry the information . These pits are placed in rows of the same width and equal distance , which form a diffraction grating on the mirror surface of the CD .

OBSERVATIONS:

Part - I : To calculate the track pitch or diffraction grating of a CD 

S. No	D ( cm )	Distance between two corresponding maximas  X ( cm )	Tanθ =  x /D	θ ( in degrees )	Sin θ	d= λ/ Sin θ ( μm )
1	37.4	13.9	0.371	20.35	0.347	1.53
2	31.5	12.6	0.400	21.80	0.371	1.43
3	32	11.8	0.368	20.20	0.345	1.54
4	31	10.8	0.348	19.18	0.328	1.62
5.	33	12.5	0.378	20.70	0.353	1.50

Results:  Mean of the grating constant= (1.53 +1.43 + 1.54 +1.62 + 1.50 ) /5

= 1.53 μm

Track Pitch ( Experimentally ) = 1.53 μm

Track Pitch ( Actual ) = 1.6 μm

Error = 0.07 μm

Part - II: Finding unknown wavelength

S. No	D ( cm )	Distance between two consecutive maximas (cm)	Tanθ= x/D	θ ( in degrees)	Sin θ	λ= d Sin θ (nm)
1.	100	48.15	0.48	25.64	0.43	657.9

Unknown wavelength : 657.9 nm

Precautions: 

Follow the safety rules while working with the laser beam .

 Experimental Set- Up :      

Diffraction Pattern using CD

Credits : My Students 

1. Rucha Kasture

2. Archit Malhotra

3. Vidushi Saxena