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Question 1. Which quantity best describes the total path traveled by an object regardless of direction? A) Displacement B) Distance C) Velocity D) Acceleration Answer: B Explanation: Distance is a scalar that measures the length of the path taken, independent of direction. Question 2. An object moves 5 m east and then 3 m west. What is its net displacement? A) 8 m east B) 2 m east C) 8 m west D) 2 m west Answer: B Explanation: Displacement = final position – initial position = (5 m E – 3 m W) = 2 m east. Question 3. The instantaneous velocity of a particle is the derivative of which function with respect to time? A) Acceleration B) Distance C) Displacement D) Speed Answer: C Explanation: Instantaneous velocity = d(displacement)/dt.
Question 4. A car’s speedometer reads 60 km/h. Which statement is true? A) The car’s velocity is 60 km/h north. B) The car’s speed is a scalar quantity. C) The car’s acceleration is 60 km/h². D) The car’s displacement equals 60 km. Answer: B Explanation: Speed is the magnitude of velocity and has no direction, making it a scalar. Question 5. If an object’s velocity changes from 10 m/s to 30 m/s in 5 s, what is its average acceleration? A) 4 m/s² B) 5 m/s² C) 10 m/s² D) 20 m/s² Answer: A Explanation: Average acceleration = Δv/Δt = (30−10)/5 = 4 m/s². Question 6. Which of the following describes uniform acceleration? A) Acceleration varies with time. B) Acceleration is zero. C) Acceleration is constant. D) Acceleration depends on velocity. Answer: C Explanation: Uniform acceleration means the acceleration value does not change over time.
Question 10. An object starts from rest and accelerates uniformly at 3 m/s² for 4 s. What distance does it travel? A) 12 m B) 24 m C) 48 m D) 64 m Answer: B Explanation: Using s = ut + ½at², with u = 0 → s = ½·3·4² = 24 m. Question 11. Which equation relates final velocity squared to initial velocity, acceleration, and displacement? A) v = u + at B) s = ut + ½at² C) v² = u² + 2as D) s = ½(u+v)t Answer: C Explanation: v² = u² + 2as is the third kinematic equation. Question 12. A ball is thrown upward with initial speed 20 m/s. Ignoring air resistance, what is its maximum height? (g = 10 m/s²) A) 10 m B) 20 m C) 30 m D) 40 m Answer: B
Explanation: At max height v = 0 → 0 = 20² – 2·10·h → h = 400/20 = 20 m. Question 13. In the equation s = ½(u+v)t, what does the term (u+v)/2 represent? A) Average acceleration B) Average velocity C) Instantaneous velocity D) Displacement rate Answer: B Explanation: (u+v)/2 is the arithmetic mean of initial and final velocities, i.e., average velocity for constant acceleration. Question 14. Which of the following is NOT a scalar quantity? A) Speed B) Distance C) Displacement D) Mass Answer: C Explanation: Displacement has both magnitude and direction; it is a vector. Question 15. A particle moves with a constant speed of 5 m/s for 10 s. What is its displacement? A) 5 m B) 10 m C) 50 m D) 0 m Answer: C
C) Reducing antenna gain D) Using a single‑beam antenna Answer: B Explanation: Fuzzy‑logic algorithms like NIMA assign confidence values to differentiate true atmospheric signals from clutter. Question 19. To obtain the horizontal wind vector (u, v) from four radial velocity measurements (north, east, south, west), which mathematical operation is essential? A) Simple averaging B) Vector decomposition using trigonometric functions C) Integration over time D) Multiplication by the radar wavelength Answer: B Explanation: Radial velocities are projected onto Cartesian axes; solving a set of linear equations yields u and v. Question 20. In a polar coordinate system used by Doppler radars, the azimuth angle is measured from which direction? A) East B) North C) West D) South Answer: B Explanation: Radar azimuth is conventionally measured clockwise from true north. Question 21. The confidence value in the NWCA algorithm is primarily based on which parameter?
A) Beam width B) Signal‑to‑noise ratio (SNR) C) Antenna height D) Pulse length Answer: B Explanation: Higher SNR yields higher confidence that the measured velocity represents true atmospheric motion. Question 22. According to Newton’s first law, an object will maintain its state of motion unless acted upon by a: A) Conservative force B) Net external force C) Internal force D) Gravitational field only Answer: B Explanation: Inertia resists changes in motion unless a net external force is present. Question 23. A linear actuator of mass 2 kg is accelerated from rest to 0.5 m/s². What force must the motor supply (ignore friction)? A) 0.25 N B) 1 N C) 2 N D) 4 N Answer: C Explanation: F = ma → 2 kg × 0.5 m/s² = 1 N (Oops correction: 2 kg × 0.5 = 1 N). The correct answer is B. Answer: B
Answer: D Explanation: Leadscrews have higher mechanical advantage (load capacity) and better positioning accuracy, though they are less efficient than belts. Question 27. In tribology, the coefficient of friction between two sliding surfaces is reduced primarily by: A) Increasing surface roughness B) Adding a lubricating film C) Raising the normal load D) Decreasing temperature Answer: B Explanation: Lubricants form a film that separates surfaces, lowering friction. Question 28. A displacement‑time graph with a straight, horizontal line indicates: A) Constant positive velocity B) Constant negative velocity C) Zero velocity (object at rest) D) Constant acceleration Answer: C Explanation: Horizontal line → slope = 0 → velocity = 0. Question 29. On a velocity‑time graph, the area under the curve between t₁ and t₂ represents: A) Average velocity B) Net displacement C) Acceleration
D) Instantaneous speed at t₁ Answer: B Explanation: Integral of velocity over time yields displacement. Question 30. A ticker‑timer produces equally spaced dots every 0.02 s. If the distance between two successive dots is 4 mm, what is the object's speed? A) 0.08 m/s B) 0.2 m/s C) 0.4 m/s D) 2 m/s Answer: C Explanation: Speed = distance/time = 0.004 m / 0.02 s = 0.2 m/s. Wait, 0.004 m / 0.02 s = 0.2 m/s. So answer B. Answer: B Explanation: Convert 4 mm to meters (0.004 m) and divide by 0.02 s → 0.2 m/s. Question 31. In radar wind profiling, “ground clutter” primarily originates from: A) Atmospheric turbulence B) Reflections off terrain or stationary objects C) Thermal noise in the receiver D) Beam sidelobes Answer: B Explanation: Ground clutter is the return from non‑moving surfaces near the radar. Question 32. To verify NWCA wind estimates, which reference instrument provides the most comparable data?
Question 35. In a pneumatic linear cylinder, the force generated is proportional to: A) Cylinder bore area only B) Supply pressure only C) Product of bore area and supply pressure D) Supply temperature Answer: C Explanation: F = P × A; both pressure and area determine the output force. Question 36. The term “ball conformity” in linear guides refers to: A) The spherical shape of the rolling elements B) The matching of ball size to groove radius to reduce contact stress C) The alignment of guide rails D) The lubrication regime Answer: B Explanation: Conformity ensures the ball contacts the raceway over an optimal area, minimizing Hertzian stress. Question 37. When a linear actuator moves with a constant velocity, its acceleration is: A) Positive B) Negative C) Zero D) Undefined Answer: C Explanation: Constant velocity implies no change in speed, thus zero acceleration.
Question 38. Which graph best represents uniformly accelerated motion starting from rest? A) Linear displacement‑time graph B) Parabolic displacement‑time graph C) Horizontal velocity‑time graph D) Exponential velocity‑time graph Answer: B Explanation: With constant acceleration, displacement varies as s = ½at², a parabola. Question 39. In the equation v² = u² + 2as, if the displacement s is negative, what does this imply about the motion? A) The object is moving forward. B) The object is decelerating while moving forward. C) The object is moving opposite to the initial direction. D) The equation is invalid for negative s. Answer: C Explanation: Negative s indicates motion opposite to the chosen positive direction. Question 40. A radar beam is tilted 30° upward from horizontal. The measured radial velocity is 10 m/s toward the radar. What is the vertical component of the wind? (Assume only vertical motion contributes to the radial component.) A) 5 m/s upward B) 5 m/s downward C) 8.66 m/s upward D) 8.66 m/s downward Answer: C
A) 3000 rpm B) 1500 rpm C) 750 rpm D) 500 rpm Answer: C Explanation: Speed ratio is inverse of pulley size ratio, so driven speed = driver speed / 2 = 750 rpm. Question 44. Which of the following statements about pneumatic versus hydraulic actuation is correct? A) Pneumatics generally provide higher force density. B) Hydraulics are compressible, leading to faster response. C) Pneumatics are cleaner but offer lower force per unit volume. D) Hydraulic fluids have lower viscosity than air. Answer: C Explanation: Air is compressible and provides lower force density; hydraulics deliver higher forces. Question 45. In a displacement‑time graph, a straight line with a negative slope indicates: A) Constant positive velocity B) Constant negative velocity (motion opposite to positive direction) C) Acceleration D) No motion Answer: B Explanation: Negative slope = negative constant velocity.
Question 46. When analyzing a velocity‑time graph, the area under a segment where velocity is negative yields: A) Positive displacement B) Negative displacement (movement opposite to positive axis) C) Zero displacement D) Acceleration magnitude Answer: B Explanation: Integration of negative velocity gives negative displacement. Question 47. A linear encoder provides 1000 pulses per revolution of a motor shaft coupled to a 10 mm lead screw. What linear resolution (mm per pulse) does the system have? A) 0.01 mm B) 0.1 mm C) 1 mm D) 10 mm Answer: B Explanation: One revolution moves 10 mm; 1000 pulses per rev → 10 mm / 1000 = 0.01 mm per pulse. Wait that's 0.01 mm. So answer A. Answer: A Explanation: 10 mm / 1000 = 0.01 mm per pulse. Question 48. In a linear guide, differential slip between the ball and raceway leads to: A) Increased load capacity B) Decreased wear and longer life C) Higher friction and heat generation D) Reduced positional accuracy
Answer: A Explanation: Negative radial velocity conventionally means the target is moving away from the radar. Question 52. In the NWCA algorithm, a low signal‑to‑noise ratio (SNR) will most likely result in: A) Higher confidence values B) Lower confidence values and possible data rejection C) Increased measured wind speed D) No effect on the output Answer: B Explanation: Low SNR reduces confidence that the measurement reflects true wind. Question 53. If a linear guide experiences a load of 200 N and the guide’s static friction coefficient is 0.03, what is the minimum motor force required to start motion? A) 6 N B) 2 N C) 0.6 N D) 60 N Answer: A Explanation: Friction force = μ × N = 0.03 × 200 N = 6 N; motor must exceed this. Question 54. Which of the following best describes a “lead” in a leadscrew? A) The diameter of the screw B) The distance the nut travels in one full rotation C) The material hardness of the screw D) The angle of the thread flank
Answer: B Explanation: Lead is the linear travel per revolution. Question 55. A linear actuator moves 0.5 m in 2 s with constant acceleration from rest. What is the acceleration? A) 0.125 m/s² B) 0.25 m/s² C) 0.5 m/s² D) 1 m/s² Answer: B Explanation: Using s = ½at² → 0.5 = 0.5 a (2)² → 0.5 = 2a → a = 0.25 m/s². Question 56. In a velocity‑time graph, a straight line passing through the origin with slope 3 m/s² represents: A) Constant velocity of 3 m/s B) Constant acceleration of 3 m/s² C) Constant displacement of 3 m D) Zero acceleration Answer: B Explanation: Slope of velocity‑time graph = acceleration. Question 57. Which of the following is a direct consequence of Newton’s second law? A) Momentum is conserved in isolated systems. B) Force equals mass times acceleration. C) Every action has an equal and opposite reaction.
