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Question 1. Which quantity is always a scalar? A) Displacement B) Velocity C) Distance D) Acceleration Answer: C Explanation: Distance has magnitude only and no direction, making it a scalar. Displacement, velocity, and acceleration are vectors.
Question 2. If a car moves at a constant speed of 20 m/s for 10 seconds, what is the distance traveled? A) 2 m B) 200 m C) 0.5 m D) 20 m Answer: B Explanation: Distance = speed × time = 20 m/s × 10 s = 200 m.
Question 3. Which graph shows constant acceleration? A) A horizontal position-time graph B) A straight, sloped position-time graph C) A straight, sloped velocity-time graph D) A curved velocity-time graph Answer: C Explanation: A straight, sloped velocity-time graph indicates constant acceleration (constant change in velocity).
Question 4. What is the acceleration of a freely falling object near Earth's surface (neglecting air resistance)? A) 0 m/s² B) 4.9 m/s² C) 9.8 m/s² D) 98 m/s² Answer: C Explanation: The acceleration due to gravity near Earth's surface is approximately 9.8 m/s².
Question 7. Two vectors of magnitude 5 units each are added at a 90° angle. What is the magnitude of the resultant? A) 5 B) 10 C) 7. D) 25 Answer: C Explanation: Resultant = √(5² + 5²) = √50 ≈ 7.1 units.
Question 8. A projectile is launched at an angle. What is its acceleration at the top of its trajectory? A) Zero B) 9.8 m/s² upwards C) 9.8 m/s² downwards D) Depends on launch velocity Answer: C
Explanation: The only acceleration is gravity, always 9.8 m/s² downward.
Question 9. If a boat moves east at 3 m/s in a river flowing north at 4 m/s, what is the boat's speed relative to the ground? A) 5 m/s B) 7 m/s C) 1 m/s D) 0 m/s Answer: A Explanation: Use Pythagoras: speed = √(3² + 4²) = 5 m/s.
Question 10. What does the slope of a position-time graph represent? A) Acceleration B) Distance C) Velocity D) Force Answer: C
Explanation: Gravitational attraction between Earth and the satellite provides the centripetal force for orbit.
Question 13. If the net force on an object is zero, which statement is true? A) The object must be at rest B) The object must be moving at constant velocity C) The object must be accelerating D) The object must be slowing down Answer: B Explanation: Zero net force means no acceleration; the object maintains its velocity (which could be zero or constant).
Question 14. Which diagram correctly represents Newton’s Third Law? A) Two forces acting in the same direction on one object B) Two equal and opposite forces acting on two interacting objects C) Two unequal forces on the same object D) No forces present
Answer: B Explanation: Newton’s Third Law states that forces come in equal and opposite action-reaction pairs on different objects.
Question 15. What is the net force on a 2 kg object accelerating at 3 m/s²? A) 0.67 N B) 1.5 N C) 6 N D) 5 N Answer: C Explanation: F = ma = 2 kg × 3 m/s² = 6 N.
Question 16. A 10 kg mass weighs how much on Earth? A) 10 N B) 9.8 N C) 98 N D) 100 N
Explanation: Static friction acts while there is no motion between surfaces; kinetic friction acts during sliding.
Question 19. In an Atwood machine with equal masses, what happens when the system is released? A) It accelerates upward B) It accelerates downward C) It remains in equilibrium D) It oscillates Answer: C Explanation: With equal masses, the forces balance, so the system does not accelerate.
Question 20. Which of the following is a non-contact force? A) Tension B) Gravitational C) Normal D) Friction
Answer: B Explanation: Gravitational force acts at a distance without physical contact.
Question 21. What provides the centripetal force for a car turning on a flat curve? A) Gravity B) Friction between tires and road C) Air resistance D) Normal force Answer: B Explanation: Friction between the tires and road keeps the car moving in a circle.
Question 22. What is the work done by a 10 N force moving a box 5 m horizontally? A) 2 J B) 15 J C) 50 J D) 0 J
Answer: C Explanation: KE = ½mv² = 0.5 × 4 × 100 = 200 J.
Question 25. Which of the following is not a form of potential energy? A) Gravitational B) Elastic C) Chemical D) Kinetic Answer: D Explanation: Kinetic energy is energy of motion, not stored energy.
Question 26. When only conservative forces act, what is true about mechanical energy? A) It is always increasing B) It is always decreasing C) It is not conserved D) It is conserved
Answer: D Explanation: Mechanical energy is conserved in the absence of non-conservative forces like friction.
Question 27. What is the unit for power in the SI system? A) Joule B) Watt C) Newton D) Horsepower Answer: B Explanation: Power is measured in Watts (W), where 1 W = 1 J/s.
Question 28. Which statement describes impulse? A) The rate of change of momentum B) The product of force and time C) The energy of motion D) The force per unit area
D) Explosive Answer: C Explanation: In elastic collisions, both kinetic energy and momentum are conserved.
Question 31. When a gun is fired, the bullet moves forward and the gun recoils backward. This is an example of: A) Conservation of energy B) Conservation of mass C) Conservation of momentum D) Newton's First Law Answer: C Explanation: The momentum of the system (gun + bullet) is conserved; forward momentum of the bullet is balanced by the backward momentum of the gun.
Question 32. Which of the following is a correct analogy between linear and rotational motion? A) Displacement – angular acceleration
B) Velocity – angular velocity C) Force – torque D) Both B and C Answer: D Explanation: Velocity corresponds to angular velocity; force corresponds to torque in rotational motion.
Question 33. What is torque? A) A linear force B) A force that causes translational motion C) A measure of rotational force D) A measure of inertia Answer: C Explanation: Torque is the tendency of a force to cause rotation about an axis.
Question 34. For an object in rotational equilibrium: A) The net torque is zero
Question 36. What is the value of g on a planet with twice Earth's mass and the same radius? A) 4.9 m/s² B) 9.8 m/s² C) 19.6 m/s² D) 39.2 m/s² Answer: C Explanation: g = GM/r²; doubling mass doubles g: 2 × 9.8 = 19.6 m/s².
Question 37. Which of the following is a transverse wave? A) Sound B) Water wave C) Seismic P-wave D) Compression in a spring Answer: B Explanation: Water waves are transverse, with particles moving perpendicular to wave direction. Sound and P-waves are longitudinal.
Question 38. What determines the speed of a wave on a string? A) Tension and mass per unit length B) Amplitude and frequency C) Wavelength and amplitude D) Frequency and energy Answer: A Explanation: Speed = √(tension/mass per unit length).
Question 39. The time for one complete cycle of a wave is called: A) Frequency B) Period C) Amplitude D) Wavelength Answer: B Explanation: Period is the time taken for one full cycle.
