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Question 1. Which physical quantity is defined as the rate of change of displacement with respect to time? A) Acceleration B) Velocity C) Speed D) Distance Answer: B Explanation: Velocity is the rate at which displacement changes with time, distinguishing it from speed, which is the rate of change of distance. Question 2. What does the slope of a position vs. time graph represent? A) Acceleration B) Displacement C) Velocity D) Speed Answer: C Explanation: The slope of a position-time graph gives velocity, as it shows how position changes over time. Question 3. For which type of motion are the kinematic equations applicable? A) Constant acceleration B) Variable acceleration C) Simple harmonic motion D) Uniform circular motion Answer: A Explanation: Kinematic equations are valid only when acceleration is constant. Question 4. A ball is dropped from rest. Neglecting air resistance, what is its velocity after 2 seconds? (g = 9.8 m/s²) A) 4.9 m/s
B) 9.8 m/s C) 19.6 m/s D) 39.2 m/s Answer: C Explanation: v = gt = 9.8 × 2 = 19.6 m/s. Question 5. In projectile motion, the horizontal and vertical components of velocity are: A) Dependent on each other B) Independent of each other C) Always equal D) Both zero Answer: B Explanation: The components are independent; gravity affects only the vertical component. Question 6. Which vector correctly represents the sum of two perpendicular vectors of magnitude 3 units and 4 units? A) 5 units B) 6 units C) 7 units D) 12 units Answer: A Explanation: By Pythagoras: √(3² + 4²) = 5 units. Question 7. The range of a projectile is maximum when the angle of projection with the horizontal is: A) 30° B) 45° C) 60° D) 90° Answer: B
A) Newton’s First Law B) Newton’s Second Law C) Newton’s Third Law D) Law of Gravitation Answer: C Explanation: Newton's Third Law: for every action, there is an equal and opposite reaction. Question 12. Which diagram shows all forces acting on an object? A) Kinematic diagram B) Free-body diagram C) Force field diagram D) Vector diagram Answer: B Explanation: Free-body diagrams represent all forces acting on a single object. Question 13. The gravitational force between two masses is inversely proportional to: A) Their sum B) Their product C) The square of the distance between them D) The cube of the distance between them Answer: C Explanation: Newton’s law of universal gravitation: F ∝ 1/r². Question 14. The force of static friction is: A) Always less than kinetic friction B) Always equal to kinetic friction C) Can be greater than kinetic friction D) Zero Answer: C
Explanation: Static friction can be greater than kinetic friction and adjusts up to a maximum value. Question 15. The normal force on a block resting on a horizontal surface equals: A) The block’s weight B) Zero C) The applied force D) The block’s mass Answer: A Explanation: The normal force balances the weight if no other vertical forces are present. Question 16. The restoring force of a spring is described by: A) Newton’s third law B) Hooke’s law C) Pascal’s principle D) Archimedes’ principle Answer: B Explanation: Hooke’s Law: F = - kx, where k is the spring constant. Question 17. Two blocks connected by a string are pulled across a frictionless surface. The tension in the string is greatest: A) Nearest the force B) Farthest from the force C) Same everywhere D) Zero Answer: B Explanation: The block farthest from the force supports the weight of the block(s) behind it. Question 18. The centripetal force required to keep an object moving in a circle of radius r at speed v is: A) mv
Question 22. The work-energy theorem states that net work done on an object equals: A) The object’s kinetic energy B) The change in kinetic energy C) The change in potential energy D) The object’s speed Answer: B Explanation: Net work equals the change in kinetic energy. Question 23. The kinetic energy of a 4 kg object moving at 3 m/s is: A) 6 J B) 12 J C) 18 J D) 36 J Answer: C Explanation: KE = ½mv² = ½ × 4 × 9 = 18 J. Question 24. Gravitational potential energy near the Earth’s surface is zero at: A) The Earth’s surface B) Infinity C) The object’s position D) The center of Earth Answer: B Explanation: By convention, PEg = 0 at infinity. Question 25. If only conservative forces do work, mechanical energy is: A) Lost B) Gained C) Conserved
D) Doubled Answer: C Explanation: Mechanical energy is conserved when only conservative forces act. Question 26. Power is defined as: A) Work divided by time B) Work multiplied by time C) Force divided by time D) Energy Answer: A Explanation: Power = Work/Time. Question 27. The SI unit of power is: A) Joule B) Watt C) Newton D) Pascal Answer: B Explanation: The watt (W) is the SI unit of power. Question 28. Momentum is defined as: A) Force × time B) Mass × acceleration C) Mass × velocity D) Velocity × time Answer: C Explanation: p = mv. Question 29. The impulse delivered to an object is equal to:
Explanation: Angular displacement is measured in radians. Question 33. The speed of a point on a rotating object at radius r is: A) ωr B) ω²r C) r/ω D) ω/r Answer: A Explanation: v = rω. Question 34. The torque produced by a force F at a distance r from the axis, at angle θ, is: A) rF B) rF sinθ C) F/r D) Fr cosθ Answer: B Explanation: τ = rF sinθ. Question 35. The moment of inertia of a point mass m at a distance r from an axis is: A) mr B) mr² C) m/r D) r²/m Answer: B Explanation: I = mr². Question 36. Newton’s second law for rotation is: A) τ = Iα B) τ = mr
C) τ = mα D) τ = rα Answer: A Explanation: Net torque equals moment of inertia times angular acceleration. Question 37. The angular momentum of a rotating body is: A) I/ω B) Iω C) ω/I D) I/α Answer: B Explanation: L = Iω. Question 38. In the absence of external torques, angular momentum is: A) Halved B) Doubled C) Conserved D) Lost Answer: C Explanation: Angular momentum is conserved if no external torques act. Question 39. The rotational kinetic energy of a spinning body is: A) ½Iω B) ½Iω² C) Iω² D) Iω Answer: B Explanation: KE_rot = ½Iω².
Answer: C Explanation: Period does not depend on amplitude for small oscillations (ideal SHM). Question 44. The period of a simple pendulum of length L is proportional to: A) L B) √L C) 1/√L D) 1/L Answer: B Explanation: T = 2π√(L/g); period ∝ √L. Question 45. The total mechanical energy in SHM is: A) Constant B) Increasing C) Decreasing D) Zero Answer: A Explanation: Total mechanical energy is conserved (if no damping). Question 46. In a transverse wave, particle displacement is: A) Parallel to wave motion B) Perpendicular to wave motion C) Circular D) Random Answer: B Explanation: Transverse waves have particle displacement perpendicular to wave direction. Question 47. The wave speed is equal to: A) Frequency × period
B) Wavelength × frequency C) Amplitude × period D) Amplitude × frequency Answer: B Explanation: v = λf. Question 48. When two waves superimpose and produce a larger amplitude, this is: A) Destructive interference B) Standing waves C) Constructive interference D) Reflection Answer: C Explanation: Constructive interference increases amplitude. Question 49. In a standing wave, nodes are points of: A) Maximum displacement B) Zero displacement C) Minimum frequency D) Maximum speed Answer: B Explanation: Nodes are stationary points (zero displacement). Question 50. Resonance occurs when: A) Driving frequency matches natural frequency B) Frequency is minimized C) Damping is maximum D) Wavelength is zero Answer: A Explanation: Resonance occurs when the system is driven at its natural frequency.
C) Sum of atmospheric and gauge pressure D) Zero Answer: C Explanation: Absolute pressure = atmospheric + gauge pressure. Question 55. Pascal’s principle states that: A) Pressure applied to an enclosed fluid is transmitted equally in all directions B) The force of buoyancy equals weight of displaced fluid C) Fluids flow from high to low pressure D) Pressure decreases with depth Answer: A Explanation: Pascal’s principle addresses pressure transmission in fluids. Question 56. The buoyant force on an object is equal to: A) Its weight B) The weight of fluid displaced C) The volume of object D) Zero Answer: B Explanation: Archimedes’ principle: Buoyant force = weight of fluid displaced. Question 57. An object floats if: A) Its density is greater than the fluid B) Its density equals the fluid C) Its density is less than the fluid D) It is heavier than water Answer: C Explanation: Objects float when their density is less than the fluid.
Question 58. Streamline flow in fluids is characterized by: A) Random motion B) Constant velocity at every point C) Parallel layers that do not mix D) High viscosity Answer: C Explanation: Streamlines indicate non-turbulent, smooth flow. Question 59. The continuity equation (A₁v₁=A₂v₂) reflects: A) Conservation of momentum B) Conservation of mass C) Conservation of energy D) Conservation of charge Answer: B Explanation: Continuity equation is based on mass conservation for fluids. Question 60. Bernoulli’s principle is based on: A) Conservation of mass B) Conservation of energy C) Conservation of charge D) Conservation of momentum Answer: B Explanation: Bernoulli’s equation reflects energy conservation in fluids. Question 61. The Celsius and Kelvin temperature scales have: A) Different size degrees B) The same size degree C) Degrees offset by 273. D) No difference
B) Convection C) Radiation D) All of the above Answer: A Explanation: Conduction requires contact for heat transfer. Question 66. The first law of thermodynamics is a statement of: A) Conservation of mass B) Conservation of energy C) Increase in entropy D) Conservation of charge Answer: B Explanation: ΔU = Q – W; energy cannot be created or destroyed. Question 67. The second law of thermodynamics states: A) Energy is always conserved B) Entropy of an isolated system never decreases C) Heat flows from cold to hot D) Energy is destroyed Answer: B Explanation: Entropy (disorder) increases or remains constant in isolated systems. Question 68. The third law of thermodynamics states that at absolute zero: A) Entropy is zero B) Temperature is infinite C) Pressure is zero D) Energy is infinite Answer: A Explanation: Entropy approaches zero as temperature approaches absolute zero.
Question 69. The ideal gas law is: A) PV = nRT B) PV = kT C) PV = mRT D) PV = RnT² Answer: A Explanation: The ideal gas law is PV = nRT. Question 70. The average kinetic energy of gas molecules is proportional to: A) Pressure B) Volume C) Temperature D) Mass Answer: C Explanation: KE_avg ∝ T (absolute temperature). Question 71. In an isothermal process, the temperature of a gas: A) Increases B) Decreases C) Remains constant D) Is zero Answer: C Explanation: Isothermal means constant temperature. Question 72. Electric charge is: A) Created and destroyed B) Only positive C) Conserved
