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IIT JEE Physics Practice Paper – Optics (Set 4) Instructions Total Questions: 30 | Marks: 4 each | No Negative Marking Q1. Refractive index is defined as: c/v v/c λ/v f/v Q2. Snell’s law is: n₁sinθ₁ = n₂sinθ₂ θ₁ = θ₂ n₁ = n₂ None Q3. Critical angle occurs when: Refraction angle = 90° Incident angle = 90° Both equal None Q4. Mirror formula is: 1/f = 1/v + 1/u v = u + f f = v/u None Q5. Power of lens is: 1/f f v/u None Q6. Unit of power of lens: Diopter Watt Joule Newton Q7. Total internal reflection occurs when: Denser to rarer medium Rarer to denser Same medium None Q8. Image formed by plane mirror is: Virtual and erect Real Inverted None Q9. Magnification of mirror is: -v/u v/u u/v None Q10. Dispersion of light is due to: Different refractive indices Same speed Reflection Absorption Q11. Speed of light is maximum in: Vacuum Water Glass Air Q12. Concave mirror focal length sign: Negative Positive Zero Infinite Q13. Convex mirror forms image: Virtual Real Both None Q14. Lens formula is: 1/f = 1/v – 1/u 1/f = 1/v + 1/u v = u + f None Q15. Optical fiber works on: Total internal reflection Reflection Refraction Diffraction Q16. Young’s double slit experiment proves: Wave nature of light Particle nature Energy conservation None Q17. Fringe width depends on: Wavelength Mass Charge None Q18. Diffraction occurs when: Aperture size comparable to wavelength Very large aperture No aperture None Q19. Polarization proves: Transverse nature of light Longitudinal nature Particle nature None Q20. Coherent sources have: Same frequency Different frequency Random phase None Q21. Brewster angle relates to: Polarization Diffraction Reflection None Q22. Optical path = n × distance distance 1/n None Q23. Convex lens produces real image when: Object beyond F At F Inside F None Q24. Interference maxima condition: Path difference = nλ (n+½)λ λ/2 None Q25. Diffraction pattern central maxima is: Brightest Dark Same None Q26. Wavefront is: Surface of constant phase Constant velocity Constant energy None Q27. Huygens principle explains: Wave propagation Particle motion Energy loss None Q28. Angular magnification depends on: Focal length Mass Charge None Q29. Telescope works on: Refraction Diffraction Polarization None Q30. Microscope magnification depends on: Focal length Velocity Charge None Submit Optics – IIT JEE Notes (Set 4) Refractive Index Definition Refractive index (n) is defined as the ratio of speed of light in vacuum to speed of light in a medium. Formula: n = c / v Key Insight Higher refractive index means light travels slower in that medium. Refraction and Snell’s Law Law n₁ sinθ₁ = n₂ sinθ₂ Important Points Light bends towards normal when entering denser medium and away from normal when entering rarer medium. Total Internal Reflection (TIR) Conditions 1. Light must travel from denser to rarer medium 2. Angle of incidence must be greater than critical angle Applications Optical fibers, diamond sparkle, mirage formation Mirror Formula and Magnification Formula 1/f = 1/v + 1/u Magnification m = -v/u Key Insight Negative magnification indicates inverted image. Lens Formula and Power Lens Formula 1/f = 1/v – 1/u Power of Lens P = 1/f (in meter) Unit Diopter (D) Image Formation by Lenses Convex Lens Forms real image when object is beyond focal point and virtual image when inside focal length. Concave Lens Always forms virtual, erect, and diminished image. Dispersion of Light Concept White light splits into colors due to different refractive indices for different wavelengths. Key Insight Violet deviates most, red deviates least. Interference of Light Condition Constructive interference: path difference = nλ Destructive interference: path difference = (2n+1)λ/2 Young’s Double Slit Experiment Demonstrates wave nature of light. Diffraction Concept Bending of light around edges or through small apertures. Key Insight Occurs when aperture size is comparable to wavelength. Polarization Concept Polarization proves that light is a transverse wave. Brewster’s Law tanθ = n Wavefront and Huygens Principle Wavefront A surface of constant phase. Huygens Principle Every point on a wavefront acts as a source of secondary wavelets. Optical Instruments Microscope Magnification depends on focal length of objective and eyepiece. Telescope Used for viewing distant objects, works on refraction or reflection. Important Exam Concepts Conceptual Traps Light speed changes but frequency remains constant during refraction. Magnetic field does not affect light path. JEE Strategy Focus on sign conventions, formulas, and diagram-based understanding. Practice numerical problems regularly.

IIT JEE Physics Magnetism and Electromagnetic Induction practice paper with 30 MCQs, answers, explanations and instant score. 30 Questions | 4 Marks Each | No Negative Marking Q1. Unit of magnetic field is: Tesla Weber Henry Ampere Q2. Magnetic force on moving charge is: qvB qE mv²/r IR Q3. Force on current carrying conductor is: BIL qvB IR V/L Q4. Direction of magnetic force is given by: Fleming’s Left Hand Rule Right Hand Rule Lenz Law Ohm’s Law Q5. Magnetic field due to straight wire depends on: Current Distance Both None Q6. Magnetic field at center of circular loop is: μ₀I/2R μ₀I/R μ₀I/4R μ₀IR Q7. Lorentz force depends on: Velocity Charge Magnetic field All Q8. Unit of magnetic flux is: Weber Tesla Henry Joule Q9. Faraday’s law states: emf ∝ flux emf ∝ rate of change of flux emf ∝ current emf ∝ resistance Q10. Lenz law is based on: Conservation of energy Newton law Ohm law Coulomb law Submit Magnetism & Electromagnetic Induction – IIT JEE Notes (Set 3) Magnetic Field Basics Definition A magnetic field is the region around a magnet or current-carrying conductor where magnetic force can be experienced by moving charges or magnetic materials. SI Unit The SI unit of magnetic field is Tesla (T). It is a vector quantity and has both magnitude and direction. Magnetic Force on Moving Charge Lorentz Force F = qvB sinθ The magnetic force depends on charge, velocity, magnetic field, and angle between velocity and field. Important Insight If velocity is parallel to magnetic field, force is zero. If perpendicular, force is maximum. Force on Current Carrying Conductor Formula F = BIL sinθ Where B is magnetic field, I is current, and L is length of conductor. Direction Rule Fleming’s Left Hand Rule gives the direction of force acting on the conductor. Magnetic Field Due to Current Straight Wire B ∝ I / r Magnetic field increases with current and decreases with distance from wire. Circular Loop B = μ₀I / 2R Magnetic field is strongest at the center of the loop. Magnetic Flux Definition Φ = B × A × cosθ Magnetic flux represents the number of magnetic field lines passing through a surface. Unit The SI unit of magnetic flux is Weber (Wb). Electromagnetic Induction (EMI) Faraday’s Law Induced emf is proportional to rate of change of magnetic flux. ε = – dΦ/dt Key Concept Faster change in flux produces larger induced emf. This is widely used in generators. Lenz’s Law Statement The direction of induced current opposes the cause producing it. Important Insight Lenz’s law is based on conservation of energy and prevents violation of energy principles. Induced Current Conditions Induced current is produced when there is a change in magnetic flux through a circuit. Methods to Change Flux Change magnetic field, change area, or change orientation of the loop. Self Inductance Definition Self inductance is the property of a coil to oppose change in current flowing through it. Formula ε = -L (dI/dt) Mutual Inductance Definition It is the property by which a change in current in one coil induces emf in another coil. Application Used in transformers and wireless energy transfer systems. Alternating Current Basics AC Current Current that changes direction periodically is called alternating current. Frequency In India, AC frequency is 50 Hz. Key Exam Concepts Conceptual Traps Magnetic force does no work as it is perpendicular to velocity. Electric field can do work but magnetic field cannot. JEE Strategy Focus on right-hand rules, formulas, and conceptual understanding. Practice numerical problems involving magnetic force and induction carefully.

IIT JEE Physics Electrostatics and Current Electricity practice test with 30 MCQs, solutions, and instant score. 30 Questions | 4 Marks Each | No Negative Marking Q1. SI unit of electric field is: N/C Volt Ohm Ampere Q2. Coulomb’s law force varies as: r 1/r 1/r² r² Q3. Electric field inside a conductor is: Zero Maximum Infinite Constant Q4. Potential difference is defined as: Work per charge Charge per work Energy per time Force per charge Q5. Capacitance unit is: Farad Ohm Volt Ampere Q6. Ohm’s law is: V = IR P = VI F = qE W = qV Q7. Resistance depends on: Length Area Material All of these Q8. Current is defined as: Charge/time Work/time Energy/time Voltage/time Submit Electrostatics & Current Electricity – IIT JEE Notes (Set 2) Electric Charge and Coulomb’s Law Basic Concept Electric charge is a fundamental property of matter. Charges can be positive or negative and interact through electrostatic forces. Like charges repel and unlike charges attract. Coulomb’s Law F = k × (q₁q₂ / r²) The electrostatic force is directly proportional to the product of charges and inversely proportional to the square of the distance between them. This inverse square law is very important for IIT JEE. Electric Field Definition E = F / q Electric field is the force experienced by a unit positive charge placed in the field. Important Points The unit of electric field is N/C. The direction of electric field is the direction of force on a positive charge. Inside a conductor, the electric field is zero due to redistribution of charges. Electric Potential and Potential Difference Electric Potential V = W / q Electric potential is the work done per unit charge in bringing a charge from infinity to a point. Potential Difference It is the difference in potential between two points and is responsible for the flow of current in a circuit. Capacitance Definition C = Q / V Capacitance is the ability of a conductor to store charge. Parallel Plate Capacitor C = ε₀A / d Capacitance increases with plate area and decreases with distance between plates. Electric Current Definition I = Q / t Electric current is the rate of flow of charge through a conductor. Key Concept Current is caused by drift of electrons under an electric field. Though electrons move randomly, an applied field creates a net motion. Ohm’s Law Formula V = IR It states that current is directly proportional to voltage for a conductor at constant temperature. Graph Insight The V-I graph for an ohmic conductor is a straight line, and its slope represents resistance. Resistance and Resistivity Formula R = ρL / A Resistance depends on length, area, and material of the conductor. Important Points Resistance increases with length and decreases with cross-sectional area. Resistivity is a material property and is independent of shape. Combination of Resistors Series Combination R = R₁ + R₂ + R₃ Same current flows through all resistors, and total resistance increases. Parallel Combination 1/R = 1/R₁ + 1/R₂ + 1/R₃ Voltage remains the same across resistors, and total resistance decreases. Electrical Power Formula P = VI = I²R = V²/R Electrical power is the rate at which electrical energy is consumed or converted. Important Insight Higher current or voltage increases power. These formulas are frequently used in numerical problems. Key Exam Concepts Conceptual Traps Electric field inside conductor is zero. Work done depends on angle between force and displacement. Resistance does not depend on current or voltage directly. JEE Strategy Focus on formulas, units, and conceptual clarity. Practice derivations and numerical problems regularly to strengthen understanding.

Solve 30 IIT JEE Physics Mechanics questions with answers, explanations, and instant scoring. Attempt all 30 questions. Each carries 4 marks. No negative marking. Q1. A particle moves with constant acceleration. Ratio of velocities in 1s and 2s? 1 : 2 1 : 4 2 : 1 4 : 1 Q2. Work done by gravity in a closed path is: Zero Positive Negative Infinite Q3. Dimensions of force are: MLT⁻² ML²T⁻² M²LT⁻² ML⁻¹T⁻² Q4. Angle for maximum range of projectile is: 45° 30° 60° 90° Q5. Kinetic energy is proportional to: v v² v³ 1/v Q6. Acceleration at highest point of projectile: 0 g 2g -g Q7. SI unit of momentum: kg·m/s Newton Joule Watt Q8. If net force on body is zero, motion is: Rest Uniform motion Accelerated Random Q9. Escape velocity depends on: Mass Radius Both mass and radius None Q10. Work-energy theorem relates: Force Work & kinetic energy Momentum Velocity Submit IIT JEE Physics Notes – Mechanics (Practice Paper Part 1) Mechanics forms the backbone of IIT JEE Physics, and this quiz covers several fundamental concepts that every aspirant must master. These notes consolidate the key ideas, formulas, and conceptual clarity required to solve such questions effectively. 1. Kinematics and Motion Basics In problems involving constant acceleration, velocity changes linearly with time. The key equations are: If a particle starts from rest, velocity becomes directly proportional to time (v∝tv \propto tv∝t). That’s why velocity ratios often reduce to time ratios. Graphs are extremely important: Understanding graphical interpretation is crucial for JEE. 2. Projectile Motion Projectile motion is a combination of horizontal and vertical motion: Key formulas: Maximum range occurs at 45∘45^\circ45∘.At the highest point, velocity is horizontal but acceleration is still ggg downward — a very common conceptual trap. 3. Newton’s Laws of Motion Newton’s laws define how forces affect motion: If net force is zero, acceleration is zero — but velocity may not be zero. This means the object can still move with constant velocity. 4. Work, Energy, and Power Work is defined as:W=F⋅s⋅cos⁡θW = F \cdot s \cdot \cos\thetaW=F⋅s⋅cosθ Important cases: Kinetic Energy:KE=12mv2KE = \frac{1}{2}mv^2KE=21​mv2 Potential Energy:PE=mghPE = mghPE=mgh Work-Energy Theorem:W=ΔKEW = \Delta KEW=ΔKE Power:P=WtP = \frac{W}{t}P=tW​ These formulas are frequently used in JEE problems involving motion and forces. 5. Momentum and Impulse Momentum is defined as:p=mvp = mvp=mv Impulse:Impulse=F×t=ΔpImpulse = F \times t = \Delta pImpulse=F×t=Δp This concept is important in collision problems. If a large force acts for a short time, it can still produce significant change in momentum. 6. Collisions There are two main types: Perfectly inelastic collisions involve objects sticking together. Understanding conservation laws is key for solving collision-based numerical problems. 7. Circular Motion For a body moving in a circle: Centripetal force:F=mv2rF = \frac{mv^2}{r}F=rmv2​ Direction: Always towards the center. Angular velocity:ω=vr\omega = \frac{v}{r}ω=rv​ Unit: rad/s Important insight: Even if speed is constant, velocity changes due to direction — hence acceleration exists. 8. Gravitation Gravitational force:F=GMmr2F = \frac{GMm}{r^2}F=r2GMm​ Acceleration due to gravity:g=GMR2g = \frac{GM}{R^2}g=R2GM​ If radius increases, gravity decreases (inverse square relationship). Escape velocity:ve=2GMRv_e = \sqrt{\frac{2GM}{R}}ve​=R2GM​​ It depends on both mass and radius of the planet. 9. Friction Frictional force:f=μNf = \mu Nf=μN Depends on: It does NOT depend on surface area directly. Types: Static friction adjusts itself up to a maximum value. 10. Elasticity and Hooke’s Law Hooke’s Law:F=kxF = kxF=kx Valid only within elastic limit. Beyond elastic limit, permanent deformation occurs and the law is no longer valid. 11. Rotational Mechanics Torque:τ=r×F\tau = r \times Fτ=r×F Angular momentum:L=r×pL = r \times pL=r×p Conservation of angular momentum occurs when no external torque acts. 12. Important Conceptual Insights 13. Dimensional Analysis Used to check correctness of equations. Example:Force:[F]=MLT−2[F] = MLT^{-2}[F]=MLT−2 Energy:[ML2T−2][ML^2T^{-2}][ML2T−2] This helps eliminate wrong options in MCQs. Final Strategy for IIT JEE Mechanics questions in JEE often combine multiple concepts (e.g., energy + motion + force), so integrated understanding is essential.