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Battery and Resistors

• A battery supplies 0.9 A current through a 2 Ω resistor and 0.3 A current through a 7 Ω resistor.
• The internal resistance of the battery can be calculated from this information.

Particle in Magnetic Field

• A particle of mass m and charge q moves in a circular path of radius R in a magnetic field.
• With a mass of 2m and a charge of q/2, the radius of the path would be altered in the magnetic field.

Paramagnetic Materials

• Paramagnetic materials are those that are weakly attracted by a magnetic field.
• Nickel and Cobalt are paramagnetic materials.

Galvanometer as Voltmeter

• A galvanometer with a resistance of 50 Ω is converted into a voltmeter of range (0-2V) using a 1.0 kΩ resistor.
• To convert it into a voltmeter of range (0-10 V), the resistance required needs to be calculated.

Mutual Inductance of Coils

• Two coils are placed near each other.
• A current change of 5 A/s in one coil induces an emf of 2 mV in the other, indicating mutual inductance.
• The mutual inductance of the two coils can be calculated using these values.

Electromagnetic Waves for Water Purification

• Electromagnetic waves can be used to purify water.
• Ultraviolet (UV) rays from the electromagnetic spectrum are used for the purification of water.

Compound Microscope Magnification

• Objective lens focal length: 1 cm
• Eyepiece focal length: 2 cm
• Microscope tube length: 10 cm
• Total magnification for relaxed eye viewing will need calculating for the above setup.

Stopping Potential and Frequency

• The variation of stopping potential (Vo) with frequency (v) is shown for four metals (A, B, C, D).
• With the same frequency of incident radiation, photoelectric emissions maximum kinetic energy can be observed in all metals.

Hydrogen Atom Energy Levels

• The energy of an electron in the ground state of a hydrogen atom is -13.6 eV.
• Determination of the kinetic and potential energy of the electron in the first excited state is possible.

Young's Double-Slit Experiment

• A Young's double-slit experiment is set up in a medium with a refractive index of 4/3.
• One can determine which maximum will coincide with the 6th maximum obtained if the medium is replaced by air.

Potential Energy Between Nucleons

• The potential energy between two nucleons inside a nucleus is at its minimum at a distance of approximately 1.6 fm.

Doped Silicon Crystal

• A pure silicon (Si) crystal has 5 x 10^28 atoms/m³.
• It is doped with 1 ppm concentration of antimony.
• Given a hole concentration of 4.5 x 10^9 /m³, the concentration of intrinsic charge carriers in the Si crystal can be determined.

Assertion and Reason: Charges on a Ring

• Assertion: Equal amounts of positive and negative charges are uniformly distributed on two halves of a thin circular ring. The resultant electric field at the center O of the ring is along OC.
• Reason: This is because the net potential at O is not zero.

Assertion and Reason: Energy of a Charged Particle

• Assertion: The energy of a charged particle moving in a magnetic field does not change.
• Reason: The work done by the magnetic force on the charge moving in a magnetic field is zero.

Assertion and Reason: Young's Double-Slit Experiment

• Assertion: In Young's double-slit experiment, the interference pattern is not observed when two coherent sources are infinitely close to each other.
• Reason: The fringe width is proportional to the separation between the two sources.

Assertion and Reason: Alpha Particle Scattering

• Assertion: An alpha particle is moving towards a gold nucleus. The impact parameter is maximum for the scattering angle of 180°.
• Reason: The impact parameter in an alpha particle scattering experiment does not depend upon the atomic number of the target nucleus.

Forces from Charges

• Four point charges (1 μC, -2 μC, 1 μC, -2 μC) are placed at the corners of a square with a side of 30 cm.
• Determine the net force acting on a 4 μC charge placed at the center of the square.

3 Point Charge Electric Field

• Three point charges, each 1 pC, are located at the vertices of an equilateral triangle with sides of 10 cm.
• Calculate the net electric field at the triangle's centroid.

Magnetic Force Expression

• Expression for the magnetic force F acting on a straight conductor of length L carrying current I in an external magnetic field B.
• Whether the expression remains valid when the conductor is in a zig-zag form.

Telescope Power and Magnification

• A telescope with an objective lens of focal length 150 cm and an eyepiece of focal length 5 cm.
• Calculate the magnifying power in normal adjustment, and the distance of the image formed by the objective.

Energy Levels and Wavelength

• Two energy levels of an electron in a hydrogen atom are separated by 2.55 eV.
• Find the wavelength of radiation emitted when the electron transitions from the higher energy level to the lower level.
• Identify which series of the hydrogen spectrum this line belongs to.

Earth Orbit Quantum Number

• Earth revolves around the sun in an orbit of radius 1.5 x 10^11 m at 30 km/s.
• Calculate the quantum number that characterises this revolution using Bohr's model (earth's mass = 6.0 x 10^24 kg).

Einstein's Photoelectric Equation

• Write Einstein's photoelectric equation.
• Explain the existence of threshold frequency for photoelectric emission from a given surface.
• Describe how Millikan proved the validity of Einstein's equation.

Electric Flux and Dimensions

• Define "electric flux" and provide its dimensions.
• Given a plane surface (1 cm square) in an electric field E = 100 i N/C with a unit normal vector n = 0.8 i + 0.6 k.

Lenz's Law

• State Lenz's Law and justify why, in a closed circuit, induced current opposes magnetic flux change as per energy conservation.
• Metal rod length = 2m
• Rotation frequency = 60 rev/s
• Uniform magnetic field = 2T
• Calculate the emf between the center and the end of the rod.

Ampere's Circuital Law

• State and explain Ampere's circuital law.
• Two parallel wires are 20 cm apart, carrying 5 A and 10 A in the same direction.
• Find the net magnetic field's magnitude and direction at a point midway between them.

Electron in Magnetic Field

• An electron with velocity v = (1.0 x 10^7 m/s)i + (0.5 x 10^7 m/s)j enters a region of uniform magnetic field B = (0.5 mT)j.
• Determine the radius of the electron's circular path.
• Determine whether electron traces a straight line path and if so what distance it covers in 1 revolution.

Electromagnetic Spectrum

• Identify parts of the electromagnetic spectrum known as heat waves and those absorbed by the ozone layer.
• Briefly describe one method of production and one method of detection for each.

P-N Junction Diode as Rectifier

• Describe the characteristics of a p-n junction diode that enables its use as a rectifier.
• Explain the operation of a full-wave rectifier, including a circuit diagram.

Semiconductor Properties

Explain why:

• Doped semiconductors are electrically neutral.
• No net current in a p-n junction at equilibrium.
• Reverse current in a diode is practically independent of applied voltage.

Dielectrics in Capacitors

• Dielectrics are useful for the design of capacitors.
• Molecules may be polar or non-polar.
• An electric field is established inside when a dielectric slab is placed inside an external electric field.
• The capacitance depends on the dielectric constant of the material.
• (i) Identify a polar molecule from the given options.
• (ii) Select the correct statement about dielectrics.
• (iii) Predict the effect on the stored energy when a dielectric slab is inserted into an isolated charged capacitor.
• (iv) (a) Calculate the new capacitance of an air-filled capacitor when a dielectric is inserted.
• (iv) (b) Find the ratio of stored energies when a combination of two capacitors are connected in series then in parallel.

Optical Prism Formula

μ = sin (A+ δm/2)/ sin (A/2)

• Ray of light suffers refraction and deviates from its original path.
• If the angle of incidence on the second surface is greater than the critical angle, the ray will undergo internal reflection.
• (i) Compare of the critical angle for glass vs water.
• (ii) What happens to wavelength and frequency when a ray of light enters a denser medium?
• (iii) (a) The critical angle is at a minimum for what light color?
• (iii) (b) Three prism beams of light are under minimum conditions - red ,yellow, violet. What is there angle of refraction?
• (iv) Light with √2 passes the ABC what happens to the ray of light.

Electric Dipole Equipotential Surfaces

• (i) Draw equipotential surfaces for an electric dipole.
• (ii) Show 2 point charges(Q1 and Q2 located at R1 and R2 respectively) obtain expression for electric potential of each
• (iii) Dipole molecule moment 10 *10^-30 placed in electric field of 10^-5 v/m at 60 degrees find the change in potential energy.
• (iv)(a) Thin radius use guass' law in electric field
• (iv)(b) Two long straight thin wires AB and CD 10^-6 and 20^-6

Circuit Components

• (i) What are circuit parts if given voltage divided by I and V leads 1?
• (ii) What is impedance
• (iii) Obtain conditions in LCR when impedance minimises and when wattless current flows.

Light Waves Through Huygens Principle

• (i) Plane light wave from rarer > descner on surface separate
• (ii) In youngs screen sepoatr 0/30wm screen 1.5 and wavelength find bright and light fringe

Concave Mirros

• (i) Diffraction of light drawing
• (ii) Mirror formula